Description of Organization and Business Operations	12 Months Ended
Nov. 30, 2025
Accounting Policies [Abstract]
Description of Organization and Business Operations	Note 1 — Description of Organization and Business Operations Black Hawk Acquisition Corporation (the “Company”) is a blank check company incorporated under the laws of the Cayman Islands with limited liability on September 28, 2023. The Company was formed for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses or entities (“Business Combination”). The Company is not limited to a particular industry or sector for purposes of consummating a Business Combination. The Company is an early stage and emerging growth company and, as such, the Company is subject to all of the risks associated with early stage and emerging growth companies. As of November 30, 2025, the Company had not commenced any operations. All activities through November 30, 2025 are related to the Company’s formation and the initial public offering (“IPO” as defined below), and subsequent to the IPO, identifying a target company for an initial business combination. The Company will not generate any operating revenues until after the completion of a Business Combination, at the earliest. The Company will generate non-operating income in the form of interest income from the proceeds derived from the IPO. The Company has selected November 30 as its fiscal year end. The Company’s sponsor is Black Hawk Management LLC (the “Sponsor”), a Delaware limited liability company. The registration statement for the Company’s IPO became effective on March 20, 2024. On March 22, 2024, the Company consummated the IPO of 6,900,000 units (which does not include the exercise of the over-allotment option by the underwriters in the IPO) at an offering price of $10.00 per unit (the “Public Units’), generating gross proceeds of $69,000,000. Simultaneously with the IPO, the Company sold to its Sponsor 235,500 units at $10.00 per unit (the “Private Units”) in a private placement generating total gross proceeds of $2,355,000, which is described in Note 4. Transaction costs amounted to $4,309,493, consisted of $690,000 cash underwriting, $2,415,000 deferred underwriting fees (payable only upon completion of a Business Combination), $690,000 issuance of representative shares and $514,493 other offering costs. Upon the closing of the IPO and the private placement on March 22, 2024, a total of $69,345,000 was placed in a trust account (the “Trust Account”) maintained by Continental Stock Transfer & Trust Company as a trustee and will be invested only in U.S. government treasury bills with a maturity of 185 days or less or in money market funds meeting certain conditions under Rule 2a-7 under the Investment Company Act of 1940, as amended (the “Investment Company Act”), and that invest only in direct U.S. government treasury obligations. These funds will not be released until the earlier of the completion of the initial Business Combination and the liquidation due to the Company’s failure to complete a Business Combination within the applicable period of time. The proceeds deposited in the Trust Account could become subject to the claims of the Company’s creditors, if any, which could have priority over the claims of the Company’s public shareholders. In addition, interest income earned on the funds in the Trust Account may be released to the Company to pay its income or other tax obligations. With these exceptions, expenses incurred by the Company may be paid prior to a business combination only from the net proceeds of the IPO and private placement not held in the Trust Account. Pursuant to Nasdaq listing rules, the Company’s initial Business Combination must occur with one or more target businesses having an aggregate fair market value equal to at least 80% of the value of the funds in the Trust account (excluding any deferred underwriting discounts and commissions and taxes payable on the income earned on the Trust Account), which the Company refers to as the 80% test, at the time of the execution of a definitive agreement for its initial Business Combination, although the Company may structure a Business Combination with one or more target businesses whose fair market value significantly exceeds 80% of the trust account balance. If the Company is no longer listed on Nasdaq, it will not be required to satisfy the 80% test. The Company will only complete a Business Combination if the post-transaction company owns or acquires 50% or more of the outstanding voting securities of the target or otherwise acquires a controlling interest in the target sufficient for it not to be required to register as an investment company under the Investment Company Act. The Company will provide its holders of the outstanding Public Shares (the “Public Shareholders”) with the opportunity to redeem all or a portion of their Public Shares upon the completion of a Business Combination either (i) in connection with a shareholder meeting called to approve the Business Combination or (ii) by means of a tender offer. The decision as to whether the Company will seek shareholder approval of a Business Combination or conduct a tender offer will be made by the Company, solely in its discretion. The Public Shareholders will be entitled to redeem their Public Shares for a pro rata portion of the amount then in the Trust Account (initially anticipated to be $10.00 per Public Share, plus any pro rata interest earned on the funds held in the Trust Account and not previously released to the Company to pay its franchise and income tax obligations). The Public Shares subject to redemption will be recorded at a redemption value and classified as temporary equity upon the completion of the Proposed Offering in accordance with the Accounting Standards Codification (“ASC”) Topic 480 “Distinguishing Liabilities from Equity.” The Company will proceed with a Business Combination if the Company has net tangible assets of at least $5,000,001 upon such consummation of a Business Combination and, if the Company seeks shareholder approval, a majority of the shares voted are voted in favor of the Business Combination. If a shareholder vote is not required by law and the Company does not decide to hold a shareholder vote for business or other legal reasons, the Company will, pursuant to its amended and restated memorandum and articles of association, conduct the redemptions pursuant to the tender offer rules of the U.S. Securities and Exchange Commission (“SEC”) and file tender offer documents with the SEC prior to completing a Business Combination. If, however, shareholder approval of the transaction is required by law, or the Company decides to obtain shareholder approval for business or legal reasons, the Company will offer to redeem shares in conjunction with a proxy solicitation pursuant to the proxy rules and not pursuant to the tender offer rules. Additionally, each public shareholder may elect to redeem their Public Shares irrespective of whether they vote for or against the proposed transaction. If the Company seeks shareholder approval in connection with a Business Combination, the Company’s Sponsor and any of the Company’s officers or directors that may hold Founder Shares (as defined in Note 5) (the “Initial Shareholders”) and the underwriters have agreed (a) to vote their Founder Shares, Private Shares (as defined in Note 4), Shares issued as underwriting commissions (see Note 6) and any Public Shares purchased during or after the Proposed Public Offering in favor of approving a Business Combination and (b) not to convert any shares (including the Founder Shares) in connection with a shareholder vote to approve, or sell the shares to the Company in any tender offer in connection with, a proposed Business Combination. If the Company seeks shareholder approval of a Business Combination and it does not conduct redemptions pursuant to the tender offer rules, the amended and restated memorandum and articles of association provides that a public shareholder, together with any affiliate of such shareholder or any other person with whom such shareholder is acting in concert or as a “group” (as defined under Section 13 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), will be restricted from redeeming its shares with respect to more than an aggregate of 15% or more of the Public Shares, without the prior consent of the Company. The Initial Shareholders have agreed (a) to waive their redemption rights with respect to the Founder Shares, Private Shares, and Public Shares held by them in connection with the completion of a Business Combination and (b) not to propose, or vote in favor of, an amendment to the Amended and Restated Certificate of Incorporation that would affect the substance or timing of the Company’s obligation to redeem 100% of its Public Shares if the Company does not complete a Business Combination, unless the Company provides the Public Shareholders with the opportunity to redeem their Public Shares in conjunction with any such amendment. The Company will have 15 months (or up to 18 months or up to 21 months if it extends such period) from the closing of the IPO to consummate a Business Combination (the “Combination Period”). If the Company anticipates that that it may not be able to consummate initial business combination within 15 months, the Company’s insiders or their affiliates may, but are not obligated to, extend the period of time to consummate a business combination two times by an additional three months each time (for a total of 21 months to complete a business combination) (the “Combination Period”). In order to extend the time available for the Company to consummate a Business Combination, the Sponsor or its affiliate or designees must deposit into the Trust Account $690,000 ($0.10 per Public Share) or an aggregate of $1,380,000, on or prior to the date of the applicable deadline. If the Company is unable to complete a Business Combination within the Combination Period, the Company will (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the trust account including interest (which interest shall be net of taxes payable and less up to $100,000 of interest to pay liquidation and dissolution expenses), divided by the number of then outstanding public shares, which redemption will completely extinguish public shareholders’ rights as shareholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the Company’s remaining shareholders and the Company’s board of directors, dissolve and liquidate, subject in each case to the Company’s obligations under Cayman Islands law to provide for claims of creditors and the requirements of other applicable law. The Sponsor and the other Initial Shareholders have agreed to waive their liquidation rights with respect to the Founder Shares, and Private Shares if the Company fails to complete a Business Combination within the Combination Period. However, if the Sponsor or the other Initial Shareholders acquires Public Shares in or after the IPO, such Public Shares will be entitled to liquidating distributions from the Trust Account if the Company fails to complete a Business Combination within the Combination Period. The underwriters have agreed to waive their rights to their deferred underwriting commission (see Note 6) held in the Trust Account in the event the Company does not complete a Business Combination within in the Combination Period and, in such event, such amounts will be included with the other funds held in the Trust Account that will be available to fund the redemption of the Public Shares. In the event of such distribution, it is possible that the per share value of the assets remaining available for distribution will be less than $10.05. In order to protect the amounts held in the Trust Account, the Sponsor has agreed to be liable to the Company if and to the extent any claims by a vendor for services rendered or products sold to the Company, or a prospective target business with which the Company has discussed entering into a transaction agreement, reduce the amount of funds in the Trust Account to below $10.05 per Public Share, except as to any claims by a third party who executed a valid and enforceable agreement with the Company waiving any right, title, interest or claim of any kind they may have in or to any monies held in the Trust Account and except as to any claims under the Company’s indemnity of the underwriters of Proposed Public Offering against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the “Securities Act”). Moreover, in the event that an executed waiver is deemed to be unenforceable against a third party, the Sponsor will not be responsible to the extent of any liability for such third-party claims. On March 10, 2025, the Company entered into a non-binding letter of intent (the “LOI”) with a business combination target, Vesicor Therapeutics, Inc. (“Vesicor”), regarding a potential business combination (the “Transaction”). Vesicor is a California-based early development stage biotechnology corporation focused on the development of p53-based cancer therapeutics delivered via precision-engineered microvesicles. On March 15, 2025, the Company and Vesicor executed a subsequent letter of intent with an exclusivity period extending until the last day of April 2025 (the “Exclusive LOI”). Pursuant to the LOI, Vesicor deposited two non-refundable deposits totaling $250,000 into the Company’s operating account to cover the costs related to Proposed Transaction. On April 22, 2025, BH Merger Sub, Inc. (“Merger Sub”), a wholly owned subsidiary of the Company and a Delaware corporation, was formed to be the surviving company after the merger in connection with a contemplated business combination. It has no principal operations or revenue producing activities. Business Combination Agreement On April 26, 2025, the Company entered into a Business Combination Agreement (the “Business Combination Agreement”) by and among Vesicor and Merger Sub, of which Vesicor shall reincorporate into the State of Delaware so as to migrate to and domesticate as a Delaware corporation on the day that is one (1) Business Day prior to the Closing Date. The Business Combination Agreement provides, among other things, that on the terms and subject to the conditions set forth therein, (i) the Company will de-register in the Cayman Islands and transfer by way of continuation out of the Cayman Islands and into the State of Delaware so as to migrate to and domesticate as a Delaware corporation (the “Domestication”), and (ii) following the Domestication, Merger Sub will merge with Vesicor, resulting in Vesicor being the wholly owned subsidiary of the Company, who will continue to be the listed company on the Nasdaq Stock Market and change its name to Vesicor. At the effective time of the Proposed Transaction, Vesicor’s shareholders and management will receive the right to receive a number of shares of Black Hawk’s common stock equal to the consideration ratio as further specified in the Business Combination Agreement. The shares held by certain Vesicor’s shareholders will be subject to lock-up agreements for a period of six (6) months following the closing of the Proposed Transaction, subject to certain exceptions. The Transaction values Vesicor at a pre-money equity value of $70 million. Existing Vesicor shareholders and management will not receive any cash proceeds as part of the transaction and will roll over 100% of their equity into the combined company. The Transaction, which has been approved unanimously by the boards of directors of both Black Hawk and Vesicor, is subject to regulatory approvals, the approvals by the shareholders of Black Hawk and Vesicor, respectively, and the satisfaction of certain other customary closing conditions including the approval by Nasdaq of the listing application of the combined company. The completion of the Business Combination remains subject to the satisfaction or waiver of customary closing conditions, including the effectiveness of the Registration Statement on Form S-4 and Nasdaq listing approval. There can be no assurance as to the timing of the completion of the Business Combination or that it will be completed at all. 2025 Extraordinary General Meeting The Company filed its definitive proxy statement on June 10, 2025, announcing its Extraordinary General Meeting would be held on June 20, 2025 to vote on three proposals: (i) a proposal by special resolution to amend the Second Amended and Restated Memorandum and Articles of Association to allow the Company to extend the deadline for the Combination Period by up to eighteen (18) one-month extensions, from June 22, 2025 (the “Termination Date”) to December 22, 2026, for a maximum of 36 months from the date of the Company’s initial public offering; (ii) a related proposal by special resolution to amend the Trust Agreement, dated March 20, 2024, by and between Black Hawk and Continental Stock Transfer & Trust Company, to allow for such one-month extensions, with each extension conditioned upon the deposit into the Trust Account of $0.03 per remaining public share (after redemptions) for each month extended;, and (iii) a proposal, by ordinary resolution, to adjourn the Extraordinary General Meeting, to a later date or dates, if necessary, to permit further solicitation and vote of proxies if, based upon the tabulated vote at the time of the Extraordinary General Meeting, there are not sufficient votes to approve the proposals. On June 20, 2025, the Company held its Extraordinary General Meeting which, without conducting any business was adjourned. The Extraordinary General Meeting was adjourned again on June 23, 2025; June 27, 2025; July 1, 2025; and July 3, 2025 in order to solicit additional votes on the matters listed in the notice of Extraordinary General Meeting and the proxy statement, particularly the Trust Amendment Proposal (further described below). Also on June 20, 2025, the Company filed a supplemental proxy statement revising the language of the Trust Amendment Proposal. Specifically, the original language referencing deposits of “up to $55,000 per one-month extension” was removed and replaced with a new structure. As revised, the proposal allows Black Hawk to extend the Termination Date up to eighteen (18) times, each for an additional one (1) month, from the current Termination Date to December 22, 2026, by depositing into the Trust Account $0.033 per remaining public share (after redemptions) for each monthly extension, in accordance with the Company’s Trust Agreement, dated March 20, 2024, with Continental Stock Transfer & Trust Company, as trustee. On July 7, 2025, the Company filed a supplemental proxy statement further amending the Extension Proposal. The amendment revised the proposed termination date from June 22, 2025 to December 22, 2026, and modified the terms of the Trust Agreement Amendment Proposal. Under the revised terms, the Company may extend the deadline to consummate a business combination by up to eighteen (18) one-month periods, with each extension conditioned upon a deposit of $150,000 per month into the Trust Account, in accordance with the Investment Management Trust Agreement, dated March 20, 2024, between the Company and Continental Stock Transfer & Trust Company. The Company held its Extraordinary General Meeting on July 8, 2025, at which shareholders approved the Extension Proposal and related amendments to Black Hawk’s governing documents and Trust Agreement. As a result, Black Hawk now has the ability to extend the business combination deadline monthly through December 22, 2026, subject to making the required $150,000 monthly deposits into the Trust Account. In connection with the Extraordinary General Meeting, holders of 4,775,923 public ordinary shares exercised their redemption rights, resulting in a total payment of approximately $51.0 million (at approximately $10.68 per share) from the Trust Account. Following the redemptions, approximately $22.7 million remains in the Trust Account, and 2,124,077 public ordinary shares remain issued and outstanding. Extension Payment In connection with the Extension, the Sponsor agreed to make Extension Payment following the approval and implementation of the Extension. Beginning on June 22, 2025 until December 22, 2026, Black Hawk may elect to extend the date by which Black Hawk has to consummate a business combination month-by-month each time for a total of up to eighteen times by depositing $150,000 for each such one-month extension into Black Hawk’s Trust Account. On July 15, 2025, Black Hawk exercised its first extension by depositing $150,000 into the Trust Account to extend the deadline to complete the Business Combination from June 22, 2025 to July 22, 2025. The Company has exercised monthly extensions beginning June 22, 2025 by depositing $150,000 into the Trust Account for each applicable extension period. As discussed above, certain extension payments due in December 2025 and January 2026 were funded after their respective due dates. As of the issuance date of these financial statements, the Company is current with respect to its extension payments. Going Concern Consideration As of November 30, 2025, the Company had $39,521 in cash and working capital deficit of $1,431,443. The Company’s liquidity needs prior to the consummation of the IPO had been satisfied through a payment from the Sponsor of $25,000 for the Founder Shares and the loan under an unsecured promissory note from the Sponsor of $250,000 (see Note 5). The Company has incurred and expects to continue to incur significant professional costs to remain as a publicly traded company and to incur significant transaction costs in pursuit of the consummation of a Business Combination. In connection with the Company’s assessment of going concern considerations in accordance with Financial Accounting Standard Board’s Accounting Standards Update (“ASU”) 2014-15, “Disclosures of Uncertainties about an Entity’s Ability to Continue as a Going Concern,” management has determined that these conditions raise substantial doubt about the Company’s ability to continue as a going concern. In addition, if the Company is unable to complete a Business Combination within the Combination Period, the Company’s board of directors would proceed to commence voluntary liquidation and thereby a formal dissolution of the Company. There is no assurance that the Company’s plans to consummate a Business Combination will be successful within the Combination Period. As a result, management has determined that such additional condition also raises substantial doubt about the Company’s ability to continue as a going concern. The financial statements do not include any adjustments that might result from the outcome of this uncertainty. Risks and Uncertainties Various social and political circumstances in the U.S. and around the world (including rising trade tensions between the U.S. and China, and other uncertainties regarding actual and potential shifts in the U.S. and foreign, trade, economic and other policies with other countries), may contribute to increased market volatility and economic uncertainties or deterioration in the U.S. and worldwide. As a result of these circumstances and the ongoing Russia/Ukraine, Hamas/Israel conflicts and/or other future global conflicts, the Company’s ability to consummate a Business Combination, or the operations of a target business with which the Company ultimately consummates a Business Combination, may be materially and adversely affected. In addition, the Company’s ability to consummate a transaction may be dependent on the ability to raise equity and debt financing which may be impacted by these events, including as a result of increased market volatility, or decreased market liquidity in third-party financing being unavailable on terms acceptable to the Company or at all. The impact of this action and related sanctions on the world economy and the specific impact on the Company’s financial position, results of operations and/or ability to consummate a Business Combination are not yet determinable. The unaudited financial statements do not include any adjustments that might result from the outcome of these risks and uncertainties.

Description of Organization and Business Operations

12 Months Ended

Nov. 30, 2025

Description of Organization and Business Operations

Note 1 — Description of Organization and Business Operations

Black Hawk Acquisition Corporation (the “Company”) is a blank check company incorporated under the laws of the Cayman Islands with limited liability on September 28, 2023. The Company was formed for the purpose of effecting a merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses or entities (“Business Combination”). The Company is not limited to a particular industry or sector for purposes of consummating a Business Combination. The Company is an early stage and emerging growth company and, as such, the Company is subject to all of the risks associated with early stage and emerging growth companies.

As of November 30, 2025, the Company had not commenced any operations. All activities through November 30, 2025 are related to the Company’s formation and the initial public offering (“IPO” as defined below), and subsequent to the IPO, identifying a target company for an initial business combination. The Company will not generate any operating revenues until after the completion of a Business Combination, at the earliest. The Company will generate non-operating income in the form of interest income from the proceeds derived from the IPO. The Company has selected November 30 as its fiscal year end.

The Company’s sponsor is Black Hawk Management LLC (the “Sponsor”), a Delaware limited liability company.

The registration statement for the Company’s IPO became effective on March 20, 2024. On March 22, 2024, the Company consummated the IPO of 6,900,000 units (which does not include the exercise of the over-allotment option by the underwriters in the IPO) at an offering price of $10.00 per unit (the “Public Units’), generating gross proceeds of $69,000,000. Simultaneously with the IPO, the Company sold to its Sponsor 235,500 units at $10.00 per unit (the “Private Units”) in a private placement generating total gross proceeds of $2,355,000, which is described in Note 4.

Transaction costs amounted to $4,309,493, consisted of $690,000 cash underwriting, $2,415,000 deferred underwriting fees (payable only upon completion of a Business Combination), $690,000 issuance of representative shares and $514,493 other offering costs.

Upon the closing of the IPO and the private placement on March 22, 2024, a total of $69,345,000 was placed in a trust account (the “Trust Account”) maintained by Continental Stock Transfer & Trust Company as a trustee and will be invested only in U.S. government treasury bills with a maturity of 185 days or less or in money market funds meeting certain conditions under Rule 2a-7 under the Investment Company Act of 1940, as amended (the “Investment Company Act”), and that invest only in direct U.S. government treasury obligations. These funds will not be released until the earlier of the completion of the initial Business Combination and the liquidation due to the Company’s failure to complete a Business Combination within the applicable period of time. The proceeds deposited in the Trust Account could become subject to the claims of the Company’s creditors, if any, which could have priority over the claims of the Company’s public shareholders. In addition, interest income earned on the funds in the Trust Account may be released to the Company to pay its income or other tax obligations. With these exceptions, expenses incurred by the Company may be paid prior to a business combination only from the net proceeds of the IPO and private placement not held in the Trust Account.

Pursuant to Nasdaq listing rules, the Company’s initial Business Combination must occur with one or more target businesses having an aggregate fair market value equal to at least 80% of the value of the funds in the Trust account (excluding any deferred underwriting discounts and commissions and taxes payable on the income earned on the Trust Account), which the Company refers to as the 80% test, at the time of the execution of a definitive agreement for its initial Business Combination, although the Company may structure a Business Combination with one or more target businesses whose fair market value significantly exceeds 80% of the trust account balance. If the Company is no longer listed on Nasdaq, it will not be required to satisfy the 80% test. The Company will only complete a Business Combination if the post-transaction company owns or acquires 50% or more of the outstanding voting securities of the target or otherwise acquires a controlling interest in the target sufficient for it not to be required to register as an investment company under the Investment Company Act.

The Company will provide its holders of the outstanding Public Shares (the “Public Shareholders”) with the opportunity to redeem all or a portion of their Public Shares upon the completion of a Business Combination either (i) in connection with a shareholder meeting called to approve the Business Combination or (ii) by means of a tender offer. The decision as to whether the Company will seek shareholder approval of a Business Combination or conduct a tender offer will be made by the Company, solely in its discretion. The Public Shareholders will be entitled to redeem their Public Shares for a pro rata portion of the amount then in the Trust Account (initially anticipated to be $10.00 per Public Share, plus any pro rata interest earned on the funds held in the Trust Account and not previously released to the Company to pay its franchise and income tax obligations). The Public Shares subject to redemption will be recorded at a redemption value and classified as temporary equity upon the completion of the Proposed Offering in accordance with the Accounting Standards Codification (“ASC”) Topic 480 “Distinguishing Liabilities from Equity.”

The Company will proceed with a Business Combination if the Company has net tangible assets of at least $5,000,001 upon such consummation of a Business Combination and, if the Company seeks shareholder approval, a majority of the shares voted are voted in favor of the Business Combination. If a shareholder vote is not required by law and the Company does not decide to hold a shareholder vote for business or other legal reasons, the Company will, pursuant to its amended and restated memorandum and articles of association, conduct the redemptions pursuant to the tender offer rules of the U.S. Securities and Exchange Commission (“SEC”) and file tender offer documents with the SEC prior to completing a Business Combination. If, however, shareholder approval of the transaction is required by law, or the Company decides to obtain shareholder approval for business or legal reasons, the Company will offer to redeem shares in conjunction with a proxy solicitation pursuant to the proxy rules and not pursuant to the tender offer rules. Additionally, each public shareholder may elect to redeem their Public Shares irrespective of whether they vote for or against the proposed transaction. If the Company seeks shareholder approval in connection with a Business Combination, the Company’s Sponsor and any of the Company’s officers or directors that may hold Founder Shares (as defined in Note 5) (the “Initial Shareholders”) and the underwriters have agreed (a) to vote their Founder Shares, Private Shares (as defined in Note 4), Shares issued as underwriting commissions (see Note 6) and any Public Shares purchased during or after the Proposed Public Offering in favor of approving a Business Combination and (b) not to convert any shares (including the Founder Shares) in connection with a shareholder vote to approve, or sell the shares to the Company in any tender offer in connection with, a proposed Business Combination.

If the Company seeks shareholder approval of a Business Combination and it does not conduct redemptions pursuant to the tender offer rules, the amended and restated memorandum and articles of association provides that a public shareholder, together with any affiliate of such shareholder or any other person with whom such shareholder is acting in concert or as a “group” (as defined under Section 13 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), will be restricted from redeeming its shares with respect to more than an aggregate of 15% or more of the Public Shares, without the prior consent of the Company.

The Initial Shareholders have agreed (a) to waive their redemption rights with respect to the Founder Shares, Private Shares, and Public Shares held by them in connection with the completion of a Business Combination and (b) not to propose, or vote in favor of, an amendment to the Amended and Restated Certificate of Incorporation that would affect the substance or timing of the Company’s obligation to redeem 100% of its Public Shares if the Company does not complete a Business Combination, unless the Company provides the Public Shareholders with the opportunity to redeem their Public Shares in conjunction with any such amendment.

The Company will have 15 months (or up to 18 months or up to 21 months if it extends such period) from the closing of the IPO to consummate a Business Combination (the “Combination Period”). If the Company anticipates that that it may not be able to consummate initial business combination within 15 months, the Company’s insiders or their affiliates may, but are not obligated to, extend the period of time to consummate a business combination two times by an additional three months each time (for a total of 21 months to complete a business combination) (the “Combination Period”). In order to extend the time available for the Company to consummate a Business Combination, the Sponsor or its affiliate or designees must deposit into the Trust Account $690,000 ($0.10 per Public Share) or an aggregate of $1,380,000, on or prior to the date of the applicable deadline.

If the Company is unable to complete a Business Combination within the Combination Period, the Company will (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the trust account including interest (which interest shall be net of taxes payable and less up to $100,000 of interest to pay liquidation and dissolution expenses), divided by the number of then outstanding public shares, which redemption will completely extinguish public shareholders’ rights as shareholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the Company’s remaining shareholders and the Company’s board of directors, dissolve and liquidate, subject in each case to the Company’s obligations under Cayman Islands law to provide for claims of creditors and the requirements of other applicable law.

The Sponsor and the other Initial Shareholders have agreed to waive their liquidation rights with respect to the Founder Shares, and Private Shares if the Company fails to complete a Business Combination within the Combination Period. However, if the Sponsor or the other Initial Shareholders acquires Public Shares in or after the IPO, such Public Shares will be entitled to liquidating distributions from the Trust Account if the Company fails to complete a Business Combination within the Combination Period. The underwriters have agreed to waive their rights to their deferred underwriting commission (see Note 6) held in the Trust Account in the event the Company does not complete a Business Combination within in the Combination Period and, in such event, such amounts will be included with the other funds held in the Trust Account that will be available to fund the redemption of the Public Shares. In the event of such distribution, it is possible that the per share value of the assets remaining available for distribution will be less than $10.05.

In order to protect the amounts held in the Trust Account, the Sponsor has agreed to be liable to the Company if and to the extent any claims by a vendor for services rendered or products sold to the Company, or a prospective target business with which the Company has discussed entering into a transaction agreement, reduce the amount of funds in the Trust Account to below $10.05 per Public Share, except as to any claims by a third party who executed a valid and enforceable agreement with the Company waiving any right, title, interest or claim of any kind they may have in or to any monies held in the Trust Account and except as to any claims under the Company’s indemnity of the underwriters of Proposed Public Offering against certain liabilities, including liabilities under the Securities Act of 1933, as amended (the “Securities Act”). Moreover, in the event that an executed waiver is deemed to be unenforceable against a third party, the Sponsor will not be responsible to the extent of any liability for such third-party claims.

On March 10, 2025, the Company entered into a non-binding letter of intent (the “LOI”) with a business combination target, Vesicor Therapeutics, Inc. (“Vesicor”), regarding a potential business combination (the “Transaction”). Vesicor is a California-based early development stage biotechnology corporation focused on the development of p53-based cancer therapeutics delivered via precision-engineered microvesicles.

On March 15, 2025, the Company and Vesicor executed a subsequent letter of intent with an exclusivity period extending until the last day of April 2025 (the “Exclusive LOI”). Pursuant to the LOI, Vesicor deposited two non-refundable deposits totaling $250,000 into the Company’s operating account to cover the costs related to Proposed Transaction.

On April 22, 2025, BH Merger Sub, Inc. (“Merger Sub”), a wholly owned subsidiary of the Company and a Delaware corporation, was formed to be the surviving company after the merger in connection with a contemplated business combination. It has no principal operations or revenue producing activities.

Business Combination Agreement

On April 26, 2025, the Company entered into a Business Combination Agreement (the “Business Combination Agreement”) by and among Vesicor and Merger Sub, of which Vesicor shall reincorporate into the State of Delaware so as to migrate to and domesticate as a Delaware corporation on the day that is one (1) Business Day prior to the Closing Date. The Business Combination Agreement provides, among other things, that on the terms and subject to the conditions set forth therein, (i) the Company will de-register in the Cayman Islands and transfer by way of continuation out of the Cayman Islands and into the State of Delaware so as to migrate to and domesticate as a Delaware corporation (the “Domestication”), and (ii) following the Domestication, Merger Sub will merge with Vesicor, resulting in Vesicor being the wholly owned subsidiary of the Company, who will continue to be the listed company on the Nasdaq Stock Market and change its name to Vesicor. At the effective time of the Proposed Transaction, Vesicor’s shareholders and management will receive the right to receive a number of shares of Black Hawk’s common stock equal to the consideration ratio as further specified in the Business Combination Agreement. The shares held by certain Vesicor’s shareholders will be subject to lock-up agreements for a period of six (6) months following the closing of the Proposed Transaction, subject to certain exceptions.

The Transaction values Vesicor at a pre-money equity value of $70 million. Existing Vesicor shareholders and management will not receive any cash proceeds as part of the transaction and will roll over 100% of their equity into the combined company.

The Transaction, which has been approved unanimously by the boards of directors of both Black Hawk and Vesicor, is subject to regulatory approvals, the approvals by the shareholders of Black Hawk and Vesicor, respectively, and the satisfaction of certain other customary closing conditions including the approval by Nasdaq of the listing application of the combined company. The completion of the Business Combination remains subject to the satisfaction or waiver of customary closing conditions, including the effectiveness of the Registration Statement on Form S-4 and Nasdaq listing approval. There can be no assurance as to the timing of the completion of the Business Combination or that it will be completed at all.

2025 Extraordinary General Meeting

The Company filed its definitive proxy statement on June 10, 2025, announcing its Extraordinary General Meeting would be held on June 20, 2025 to vote on three proposals: (i) a proposal by special resolution to amend the Second Amended and Restated Memorandum and Articles of Association to allow the Company to extend the deadline for the Combination Period by up to eighteen (18) one-month extensions, from June 22, 2025 (the “Termination Date”) to December 22, 2026, for a maximum of 36 months from the date of the Company’s initial public offering; (ii) a related proposal by special resolution to amend the Trust Agreement, dated March 20, 2024, by and between Black Hawk and Continental Stock Transfer & Trust Company, to allow for such one-month extensions, with each extension conditioned upon the deposit into the Trust Account of $0.03 per remaining public share (after redemptions) for each month extended;, and (iii) a proposal, by ordinary resolution, to adjourn the Extraordinary General Meeting, to a later date or dates, if necessary, to permit further solicitation and vote of proxies if, based upon the tabulated vote at the time of the Extraordinary General Meeting, there are not sufficient votes to approve the proposals.

On June 20, 2025, the Company held its Extraordinary General Meeting which, without conducting any business was adjourned. The Extraordinary General Meeting was adjourned again on June 23, 2025; June 27, 2025; July 1, 2025; and July 3, 2025 in order to solicit additional votes on the matters listed in the notice of Extraordinary General Meeting and the proxy statement, particularly the Trust Amendment Proposal (further described below).

Also on June 20, 2025, the Company filed a supplemental proxy statement revising the language of the Trust Amendment Proposal. Specifically, the original language referencing deposits of “up to $55,000 per one-month extension” was removed and replaced with a new structure. As revised, the proposal allows Black Hawk to extend the Termination Date up to eighteen (18) times, each for an additional one (1) month, from the current Termination Date to December 22, 2026, by depositing into the Trust Account $0.033 per remaining public share (after redemptions) for each monthly extension, in accordance with the Company’s Trust Agreement, dated March 20, 2024, with Continental Stock Transfer & Trust Company, as trustee.

On July 7, 2025, the Company filed a supplemental proxy statement further amending the Extension Proposal. The amendment revised the proposed termination date from June 22, 2025 to December 22, 2026, and modified the terms of the Trust Agreement Amendment Proposal. Under the revised terms, the Company may extend the deadline to consummate a business combination by up to eighteen (18) one-month periods, with each extension conditioned upon a deposit of $150,000 per month into the Trust Account, in accordance with the Investment Management Trust Agreement, dated March 20, 2024, between the Company and Continental Stock Transfer & Trust Company.

The Company held its Extraordinary General Meeting on July 8, 2025, at which shareholders approved the Extension Proposal and related amendments to Black Hawk’s governing documents and Trust Agreement. As a result, Black Hawk now has the ability to extend the business combination deadline monthly through December 22, 2026, subject to making the required $150,000 monthly deposits into the Trust Account.

In connection with the Extraordinary General Meeting, holders of 4,775,923 public ordinary shares exercised their redemption rights, resulting in a total payment of approximately $51.0 million (at approximately $10.68 per share) from the Trust Account. Following the redemptions, approximately $22.7 million remains in the Trust Account, and 2,124,077 public ordinary shares remain issued and outstanding.

Extension Payment

In connection with the Extension, the Sponsor agreed to make Extension Payment following the approval and implementation of the Extension. Beginning on June 22, 2025 until December 22, 2026, Black Hawk may elect to extend the date by which Black Hawk has to consummate a business combination month-by-month each time for a total of up to eighteen times by depositing $150,000 for each such one-month extension into Black Hawk’s Trust Account. On July 15, 2025, Black Hawk exercised its first extension by depositing $150,000 into the Trust Account to extend the deadline to complete the Business Combination from June 22, 2025 to July 22, 2025. The Company has exercised monthly extensions beginning June 22, 2025 by depositing $150,000 into the Trust Account for each applicable extension period. As discussed above, certain extension payments due in December 2025 and January 2026 were funded after their respective due dates. As of the issuance date of these financial statements, the Company is current with respect to its extension payments.

Going Concern Consideration

As of November 30, 2025, the Company had $39,521 in cash and working capital deficit of $1,431,443. The Company’s liquidity needs prior to the consummation of the IPO had been satisfied through a payment from the Sponsor of $25,000 for the Founder Shares and the loan under an unsecured promissory note from the Sponsor of $250,000 (see Note 5).

The Company has incurred and expects to continue to incur significant professional costs to remain as a publicly traded company and to incur significant transaction costs in pursuit of the consummation of a Business Combination. In connection with the Company’s assessment of going concern considerations in accordance with Financial Accounting Standard Board’s Accounting Standards Update (“ASU”) 2014-15, “Disclosures of Uncertainties about an Entity’s Ability to Continue as a Going Concern,” management has determined that these conditions raise substantial doubt about the Company’s ability to continue as a going concern. In addition, if the Company is unable to complete a Business Combination within the Combination Period, the Company’s board of directors would proceed to commence voluntary liquidation and thereby a formal dissolution of the Company. There is no assurance that the Company’s plans to consummate a Business Combination will be successful within the Combination Period. As a result, management has determined that such additional condition also raises substantial doubt about the Company’s ability to continue as a going concern. The financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Risks and Uncertainties

Various social and political circumstances in the U.S. and around the world (including rising trade tensions between the U.S. and China, and other uncertainties regarding actual and potential shifts in the U.S. and foreign, trade, economic and other policies with other countries), may contribute to increased market volatility and economic uncertainties or deterioration in the U.S. and worldwide.

As a result of these circumstances and the ongoing Russia/Ukraine, Hamas/Israel conflicts and/or other future global conflicts, the Company’s ability to consummate a Business Combination, or the operations of a target business with which the Company ultimately consummates a Business Combination, may be materially and adversely affected. In addition, the Company’s ability to consummate a transaction may be dependent on the ability to raise equity and debt financing which may be impacted by these events, including as a result of increased market volatility, or decreased market liquidity in third-party financing being unavailable on terms acceptable to the Company or at all. The impact of this action and related sanctions on the world economy and the specific impact on the Company’s financial position, results of operations and/or ability to consummate a Business Combination are not yet determinable. The unaudited financial statements do not include any adjustments that might result from the outcome of these risks and uncertainties.