Form SCHEDULE 13D/A OBSIDIAN ENERGY LTD. Filed by: FrontFour Capital Group LLC

Item 3 is hereby amended and restated to read as follows: The Shares held by each of the Master Fund and FrontFour Corp. were purchased with working capital (which may, at any given time, include margin loans made by brokerage firms in the ordinary course of business). The aggregate purchase price of the 2,907,541 Shares owned directly by the Master Fund is approximately $19,280,415, including brokerage commissions. The aggregate purchase price of the 75,571 Shares owned directly by FrontFour Corp. is approximately CAD$606,214, including brokerage commissions. The aggregate purchase price of 514,272 Shares owned directly by Mr. Loukas purchased by him in the open market is approximately $1,146,759, including brokerage commissions, and were purchased with personal funds. The aggregate cost of the 921,616 Shares owned directly by Mr. Loukas that were acquired upon the exercise of stock options ("Stock Options") and the vesting of restricted share units ("RSUs") awarded to him in his capacity as an executive officer and director of the Issuer is approximately $2,938,154. Mr. Loukas also owns derivative securities of the Issuer awarded to him in his capacity as an executive officer and director of the Issuer, as set forth in further detail in Item 6. The aggregate purchase price of the 99,998 Shares beneficially owned directly by Mr. Lorber is approximately $866,408, including brokerage commissions, and were purchased with personal funds.

Item 5(a) is hereby amended and restated to read as follows: The aggregate percentage of Shares reported owned by each person named herein is based upon 67,274,326 Shares outstanding as of December 31, 2025, which is the total number of Shares outstanding as reported in the Issuer's Form 40-F filed with the Securities and Exchange Commission on February 19, 2026. As of the close of business on the date hereof, the Master Fund owned directly 2,907,541 Shares, FrontFour Corp. owned directly 75,571 Shares, Mr. Loukas beneficially owned directly 2,705,546 Shares, and Mr. Lorber beneficially owned directly 99,998 Shares, constituting approximately 4.3%, 0%, 4.0% and 0%, respectively, of the Shares outstanding. FrontFour Capital, as the investment manager of the Master Fund, may be deemed to beneficially own the 2,907,541 Shares directly owned by the Master Fund, constituting approximately 4.3% of the Shares outstanding. Mr. Loukas may be deemed to beneficially own the 2,705,546 Shares he directly beneficially owns (including 310,600 Shares underlying Stock Options that are exercisable within 60 days), constituting approximately 4.0% of the Shares outstanding. Mr. Lorber, as a managing member and principal owner of FrontFour Capital and a principal owner of FrontFour Corp., may be deemed to beneficially own the 2,983,112 Shares directly owned in the aggregate by the Master Fund and FrontFour Corp., which, together with the 99,998 Shares he directly beneficially owns, constitute approximately 4.6% of the Shares outstanding. Mr. George, as a managing member and principal owner of FrontFour Capital and a principal owner of FrontFour Corp., may be deemed to beneficially own the 2,983,112 Shares directly owned in the aggregate by the Master Fund and FrontFour Corp., which constitute approximately 4.4% of the Shares outstanding. The filing of this Schedule 13D shall not be deemed an admission that the Reporting Persons are, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, the beneficial owners of any securities of the Issuer he or it does not directly own. Each of the Reporting Persons specifically disclaims beneficial ownership of the securities reported herein that he or it does not directly own.

Item 5(b) is hereby amended and restated to read as follows: Each of the Master Fund, FrontFour Capital and Messrs. Lorber and George have shared power to vote or direct the vote of, and to dispose or direct the disposition of, the Shares owned directly by the Master Fund. Each of Messrs. Lorber and George have shared power to vote or direct the vote of, and to dispose or direct the disposition of, the Shares owned directly by FrontFour Corp. Mr. Loukas has the sole power to vote or direct the vote of, and to dispose or direct the disposition of, the Shares owned directly by him and may be deemed to have the sole power to vote or direct the vote of, and to dispose or direct the disposition of, the Shares underlying the Stock Options and RSUs directly beneficially owned by him. Mr. Lorber has the sole power to vote or direct the vote of, and to dispose or direct the disposition of, the Shares directly beneficially owned by him.

Item 5(c) is hereby amended and restated to read as follows: The transactions in the Shares of the Issuer effected by the Reporting Persons during the past sixty days are set forth on Exhibit 1 attached hereto. All of such transactions were effected in the open market except as otherwise set forth therein.

Item 5(e) is hereby amended and restated to read as follows: As of March 12, 2026, the Reporting Persons ceased to beneficially own more than 5% of the outstanding Shares.

Item 6 is hereby amended to add the following: On March 13, 2026, the Reporting Persons entered into a Joint Filing Agreement in which the Reporting Persons who will remain Reporting Persons subsequent to this Amendment No. 1 agreed to the joint filing on behalf of each of them of statements on Schedule 13D with respect to the securities of the Issuer to the extent required by applicable law. A copy of this agreement is attached hereto as Exhibit 99.1 and is incorporated herein by reference. Since the filing of the Schedule 13D, Mr. Loukas has received (i) Stock Options to purchase 753,500 Shares, (ii) PSUs referencing 150,500 Shares, and (iii) RSUs referencing 161,500 Shares. On February 27, 2026, Mr. Loukas exercised PSUs referencing 86,600 Shares, including for 43,300 Shares at a price of CAD$11.6700 and for cash consideration referencing 43,000 Shares at a price of CAD$8.3100.

Item 7 is hereby amended to add the following exhibits: 1 - Transactions in the Securities. 99.1 - Joint Filing Agreement, dated March 13, 2026