SECOND SUPPLEMENTAL INDENTURE

Exhibit 4.2

SECOND SUPPLEMENTAL INDENTURE

This Second Supplemental Indenture (this “Second Supplemental Indenture”), dated as of April 11, 2013, is by and among RAAM Global Energy Company (the “Company”), each of the guarantors party hereto (the “Guarantors”) and The Bank of New York Mellon Trust Company, N.A., as Trustee (the “Trustee”).

RECITALS

WHEREAS, the Company, the Guarantors and the Trustee are parties to that certain Indenture dated as of September 24, 2010 (the “Base Indenture”), relating to the Company’s 12.5% Senior Secured Notes due 2015 (the “Notes”), and the Base Indenture has been amended and supplemented by the First Supplemental Indenture thereto (the Base Indenture as so amended and supplemented, being referred to herein as the “Indenture”).

WHEREAS, $200,000,000 aggregate principal amount of Notes are currently outstanding;

WHEREAS, Section 9.02 of the Indenture provides that, with the consent of the Holders of at least a majority in aggregate principal amount of the Notes affected thereby then outstanding, the Company, the Guarantors and the Trustee may enter into an indenture supplemental to the Indenture for the purpose of amending or supplementing the Indenture or the Notes (subject to certain exceptions);

WHEREAS, the Company desires and has requested the Trustee to join with it and the

Guarantors in entering into this Second Supplemental Indenture for the purpose of amending the Indenture and the Notes in certain respects as permitted by Section 9.02 of the Indenture;

WHEREAS, the Company has solicited consents to this Second Supplemental

Indenture upon the terms and subject to the conditions set forth in its Consent Solicitation Statement dated April 5, 2013 and the related Consent Letter (which together, including any amendments, modifications or supplements thereto, constitute the “Consent Solicitation”);

WHEREAS, (1) the Company has received the consent of the Holders of a majority in aggregate principal amount of the outstanding Notes, all as certified by an Officers’ Certificate delivered to the Trustee simultaneously with the execution and delivery of this Second Supplemental Indenture, (2) the Company has delivered to the Trustee simultaneously with the execution and delivery of this Second Supplemental Indenture an Opinion of Counsel relating to this Second Supplemental Indenture as contemplated by Section 9.06 of the Indenture and (3) the Company and the Guarantors have satisfied all other conditions required under Article 9 of the Indenture to enable the Company, the Guarantors and the Trustee to enter into this Second Supplemental Indenture; and

WHEREAS, all other acts and things prescribed by the Indenture, by law and by the

Certificate of Incorporation and the Bylaws (or comparable constituent documents) of the Company, of the Guarantors and of the Trustee necessary to make this Second Supplemental Indenture a valid instrument legally binding on the Company, the Guarantors and the Trustee, in accordance with its terms, have been duly done and performed;

NOW, THEREFORE, to comply with the provisions of the Indenture and in consideration of the above premises, the Company, the Guarantors and the Trustee covenant and agree for the equal and proportionate benefit of the respective Holders of the Notes as follows:

ARTICLE 2

Section 2.01. Section 4.09(b) of the Indenture is hereby amended in its entirety to read as follows:

The first paragraph of this covenant will not prohibit the incurrence of any of the following items of Indebtedness (collectively, “Permitted Debt”):

(1) the incurrence by the Company or any Guarantor of Indebtedness under one or more Credit Facilities in an aggregate principal amount at any one time outstanding under this clause (1) (with letters of credit being deemed to have a principal amount equal to the maximum potential liability of the Company and its Restricted Subsidiaries thereunder) not to exceed an amount equal to the greater of (a) $75.0 million and (b) 15% of ACNTA as of the date of such incurrence;

(2) the incurrence by the Company or any of its Restricted Subsidiaries of the Existing Indebtedness;

(3) the incurrence by the Company and the Guarantors of Indebtedness represented by the Notes issued and sold in this offering and any Guarantees to be issued on the date of this Indenture and the Exchange Notes and the related Guarantees issued pursuant to the Registration Rights Agreement;

(4) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness represented by Capital Lease Obligations, mortgage financings or purchase money obligations, in each case, incurred for the purpose of financing all or any part of the purchase price or cost of construction or improvement of property, plant or equipment used in the business of the Company or such Restricted Subsidiary, in an aggregate principal amount, including all Permitted Refinancing Indebtedness incurred to refund, refinance or replace any Indebtedness incurred pursuant to this clause (4), not to exceed $10.0 million at any time outstanding;

(5) the incurrence by the Company or any of its Restricted Subsidiaries of Permitted Refinancing Indebtedness in exchange for, or the net proceeds of which are used to refund, refinance or replace Indebtedness (other than intercompany Indebtedness) that was permitted by this Indenture to be incurred under the first paragraph of this covenant or clause (2), (3), (4) or (11) of this paragraph or this clause (5);

(6) the incurrence by the Company or any of its Restricted Subsidiaries of intercompany Indebtedness between or among the Company and any of its Restricted Subsidiaries; provided, however, that:

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(a) if the Company is the obligor on such Indebtedness and a Guarantor is not the obligee, such Indebtedness must be expressly subordinated to the prior payment in full in cash of all Obligations with respect to the Notes, or if a Guarantor is the obligor on such Indebtedness and neither the Company nor another Guarantor is the obligee, such Indebtedness must be expressly subordinated to the prior payment in full in cash of all Obligations with respect to the Guarantee of such Guarantor; and

(b)(i) any subsequent issuance or transfer of Equity Interests that results in any such Indebtedness being held by a Person other than the Company or a Restricted Subsidiary of the Company and (ii) any sale or other transfer of any such Indebtedness to a Person that is neither the Company nor a Restricted Subsidiary of the Company will be deemed, in each case, to constitute an incurrence of such Indebtedness by the Company or such Restricted Subsidiary, as the case may be, that was not permitted by this clause (6);

(7) the incurrence by the Company or any of its Restricted Subsidiaries of Hedging Obligations;

(8) the guarantee by the Company or any of the Guarantors of Indebtedness of the Company or any Guarantor that was permitted to be incurred by another provision of this covenant;

(9) the incurrence by the Company or any of its Restricted Subsidiaries of obligations relating to net gas balancing positions arising in the ordinary course of business and consistent with past practice;

(10) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness in respect of bid, performance, surety and similar bonds issued for the account of the Company and any of its Restricted Subsidiaries in the ordinary course of business, including guarantees and obligations of the Company and any of its Restricted Subsidiaries with respect to letters of credit supporting such obligations (in each other than an obligation for money borrowed);

(11) Indebtedness of a Restricted Subsidiary incurred and outstanding on the date on which such Restricted Subsidiary was acquired by, or merged into, the Company or any Restricted Subsidiary (other than Indebtedness Incurred (a) to provide all or any portion of the funds utilized to consummate the transaction or series of related transactions pursuant to which such Restricted Subsidiary became a Restricted Subsidiary or was otherwise acquired by the Company or (b) otherwise in connection with, or in contemplation of, such acquisition); provided, however, that at the time such Restricted Subsidiary is acquired by the Company, the Company would have been able in Incur $1.00 of additional Indebtedness pursuant to the first paragraph of this covenant after giving effect to the incurrence of such Indebtedness pursuant to this clause (11);

(12) the incurrence by the Company or any of its Restricted Subsidiaries of Indebtedness arising from agreements of the Company or any of its Restricted Subsidiaries providing for indemnification, adjustment of purchase price or similar obligations, in each

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case, incurred or assumed in connection with the disposition of any business, assets or Capital Stock of a Subsidiary, provided that the maximum aggregate liability in respect of all such Indebtedness shall at no time exceed the gross proceeds actually received by the Company and its Restricted Subsidiaries in connection with such disposition;

(13) the incurrence by the Company or any of its Restricted Subsidiaries of additional Indebtedness in an aggregate principal amount (or accreted value, as applicable) at any time outstanding, not to exceed $15.0 million; and

(14) the incurrence by the Company or any of the Guarantors of Additional Notes and the Guarantees in respect thereof, in an aggregate principal amount at any time outstanding under this paragraph (14), not to exceed $50.0 million.

Section 2.02. Section 4.09(c) of the Indenture is hereby amended in its entirety to read as follows:

(c) For purposes of determining compliance with this Section 4.09, in the event that an item of Indebtedness (including Acquired Debt) meets the criteria of more than one of the categories of Permitted Debt described in clauses (1) through (14) above, or is entitled to be incurred pursuant to the first paragraph of this covenant, the Company will be permitted to classify (or later classify or reclassify in whole or in part in its sole discretion) such item of Indebtedness in any manner that complies with this covenant.

ARTICLE 3

Section 3.01. For all purposes of this Second Supplemental Indenture, except as otherwise defined or unless the context otherwise requires, terms used in capitalized form in this Second Supplemental Indenture and defined in the Indenture have the meanings specified in the Indenture.

Section 3.02. Except as amended hereby, the Indenture and the Notes are in all respects ratified and confirmed and all the terms shall remain in full force and effect. This Second Supplemental Indenture shall form a part of the Indenture for all purposes, and every Holder of Notes heretofore or hereafter authenticated and delivered under the Indenture shall be bound hereby and all terms and conditions of both shall be read together as though they constitute a single instrument, except that in the case of conflict the provisions of this Second Supplemental Indenture shall control.

Section 3.03. THIS SECOND SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

Section 3.04. All agreements of the Company and the Guarantors in this Second Supplemental Indenture and the Notes shall bind their respective successors. All agreements of the Trustee in this Second Supplemental Indenture shall bind its successors.

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Section 3.05. The parties may sign any number of copies of this Second Supplemental Indenture. Each signed copy shall be an original, but all of such executed copies together shall represent the same agreement. It is the express intent of the parties to be bound by the exchange of signatures on this Second Supplemental Indenture via telecopy or other form of electronic transmission.

Section 3.06. In case any one or more of the provisions in this Second Supplemental Indenture or in the Notes shall be held invalid, illegal or unenforceable, in any respect for any reason, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions shall not in any way be affected or impaired thereby, it being intended that all of the provisions hereof shall be enforceable to the full extent permitted by law.

Section 3.07. The Trustee accepts the amendments of the Indenture effected by this Second Supplemental Indenture and agrees to execute the trust created by the Indenture as hereby amended, but on the terms and conditions set forth in the Indenture, including the terms and provisions defining and limiting the liabilities and responsibilities of the Trustee, which terms and provisions shall in like manner define and limit its liabilities and responsibilities in the performance of the trust created by the Indenture as hereby amended, and without limiting the generality of the foregoing, the Trustee shall not be responsible in any manner whatsoever for or with respect to any of the recitals or statements contained herein, all of which recitals or statements are made solely by the Company and the Guarantors, and the Trustee makes no representation with respect to any such matters. Additionally, the Trustee makes no representations as to the validity or sufficiency of this Second Supplemental Indenture.

Section 3.08. The provisions of this Second Supplemental Indenture shall be effective only upon execution and delivery of this instrument by the parties hereto.

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IN WITNESS WHEREOF, the parties hereto have caused this Second Supplemental Indenture to be duly executed and attested, all as of the date first above written.

[Signature page to Second Supplemental Indenture]

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[Signature page to Second Supplemental Indenture]

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