FORM OF NEW NOTE

Exhibit 4.5

FORM OF NEW NOTE

THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES EXCEPT THAT (1) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY BE REQUIRED PURSUANT TO SECTION 2.06 OF THE INDENTURE, (2) THIS GLOBAL NOTE MAY BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.07(a) OF THE INDENTURE, (3) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT TO SECTION 2.12 OF THE INDENTURE AND (4) THIS GLOBAL NOTE MAY BE TRANSFERRED TO A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE COMPANY.

UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN DEFINITIVE FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY. UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) (“DTC”), TO THE COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS MAY BE REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR SUCH OTHER ENTITY AS MAY BE REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

CUSIP 76116A AB4

RESOLUTE ENERGY CORPORATION

8.50% Senior Notes due 2020

Resolute Energy Corporation, a Delaware corporation (the “Company”), which term includes any successor under the Indenture hereinafter referred to, for value received, promises to pay to Cede & Co., or its registered assigns, the principal sum of TWO HUNDRED FIFTY MILLION ($250,000,000) UNITED STATES DOLLARS (or such greater or lesser amount as should be reflected on the Schedule attached hereto) on May 1, 2020.

Interest Payment Dates: May 1 and November 1 of each year, commencing November 1, 2012.

Regular Record Dates: April 15 and October 15 of each year.

Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Date of Issuance:                     

IN WITNESS WHEREOF, the Company has caused this Note to be signed manually, by facsimile or by electronic image scan by its duly authorized officers.

(Form of Trustee’s Certificate of Authentication)

This is one of the 8.50% Senior Notes due 2020 described in the within-mentioned Indenture.

[Reverse Side of Note]

RESOLUTE ENERGY CORPORATION

8.50% Senior Notes due 2020

Capitalized terms used herein shall have the meanings assigned to them in the Indenture referred to below unless otherwise indicated.

1. Interest. The Company promises to pay interest on the principal amount of this Note at 8.50% per annum from the date hereof until maturity. The Company shall pay interest semi-annually in arrears on May 1 and November 1 of each year, or if any such day is not a Business Day, on the next succeeding Business Day (each an “Interest Payment Date”). Interest on the Notes shall accrue from the most recent date to which interest has been paid on the Notes (or one or more Predecessor Notes) or, if no interest has been paid, from the date of original issuance; provided that if there is no existing Default in the payment of interest, and if this Note is authenticated between a record date referred to on the face hereof and the next succeeding Interest Payment Date, interest shall accrue from such next succeeding Interest Payment Date; provided further that the first Interest Payment Date shall be November 1, 2012. The Company shall pay interest (including post-petition interest in any proceeding under any Bankruptcy Law) on overdue principal and premium, if any, from time to time on demand at a rate that is 1% per annum in excess of the rate then in effect; it shall pay interest (including post-petition interest in any proceeding under any Bankruptcy Law) on overdue installments of interest (without regard to any applicable grace periods) from time to time on demand at the same rate to the extent lawful. Interest shall be computed on the basis of a 360-day year of twelve 30-day months. If a payment date is not a Business Day, payment may be made on the next succeeding day that is a Business Day, and no interest shall accrue on such payment for the intervening period.

This Exchange Note was issued in connection with the Exchange Offer pursuant to which the 8.50% Senior Notes due 2020 in like principal amount were exchanged for Exchange Notes. The Exchange Notes rank pari passu in right of payment with the Initial Notes. For any period in which the Initial Note exchanged for this Exchange Note was outstanding, Additional Interest may be due and owing on the Initial Note in connection with the Registration Rights Agreement.

2. Method of Payment. The Company shall pay interest on the Notes (except defaulted interest, if any) to the Persons in whose name this Note (or one or more Predecessor Notes) is registered at the close of business on the April 15 or October 15 immediately preceding the Interest Payment Date, even if such Notes are canceled after such record date and on or before such Interest Payment Date, except as provided in Section 2.13 of the Indenture with respect to defaulted interest. The Notes shall be payable as to principal, premium, if any, and interest at the office or agency of the Company maintained for such purpose, or, at the option of the Company, payment of interest may be made by check mailed to the Holders at their addresses set forth in the register of Holders, and provided that payment by wire transfer of immediately available funds shall be required with respect to principal of and interest, premium, if any, on, all Global Notes and all other Notes the Holders of which shall have provided wire transfer instructions to the Company or the Paying Agent. Such payment shall be in such coin or currency of the United States of America as at the time of payment is legal tender for payment of public and private debts.

3. Paying Agent and Registrar. Initially, U.S. Bank National Association, the Trustee under the Indenture, shall act as Paying Agent and Registrar. The Company may change any Paying Agent or Registrar without notice to any Holder. The Company or any of its Subsidiaries may act in any such capacity.

4. Indenture. The Company issued the Notes under an Indenture dated as of April 25, 2012 (the “Indenture”) among the Company, the Guarantors and the Trustee. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939, as amended. The Notes are subject to all such terms, and Holders are referred to the Indenture and such Act for a statement of such terms. To the extent any provision of this Note conflicts with the express provisions of the

Indenture, the provisions of the Indenture shall govern and be controlling. The Indenture pursuant to which this Note is issued provides that an unlimited amount of Additional Notes may be issued thereunder, subject to compliance with the covenants therein.

5. Optional Redemption.

(a) On or after May 1, 2016, the Company may redeem all or a portion of the Notes, on not less than 30 nor more than 60 days’ prior notice, in amounts of $2,000 or whole multiples of $1,000 in excess thereof at the following redemption prices (expressed as percentages of the principal amount), plus accrued and unpaid interest, if any, thereon, to the applicable redemption date (subject to the rights of holders of record on relevant record dates to receive interest due on an interest payment date), if redeemed during the twelve-month period beginning on May 1 of the years indicated below:

(b) In addition, at any time and from time to time prior to May 1, 2015, the Company may use (i) the net proceeds of one or more Equity Offerings or (ii) the Net Cash Warrant Exercise Proceeds to redeem up to an aggregate of 35% of the aggregate principal amount of Notes issued under the Indenture (including the principal amount of any Additional Notes issued under the Indenture) at a redemption price equal to 108.50% of the aggregate principal amount of the Notes redeemed, plus accrued and unpaid interest, if any, to the redemption date (subject to the rights of holders of record on relevant record dates to receive interest due on an interest payment date). At least 65% of the aggregate principal amount of Notes (including the principal amount of any Additional Notes issued under the Indenture) must remain outstanding immediately after the occurrence of such redemption. In order to effect this redemption, the Company must complete such redemption no later than 180 days after the closing of the related Equity Offering.

(c) The Notes may also be redeemed, in whole or in part, at any time or from time to time prior to May 1, 2016 at the option of the Company at a redemption price equal to 100% of the principal amount of the Notes redeemed plus the Applicable Premium as of, and accrued and unpaid interest and additional interest, if any, to, the applicable redemption date (subject to the right of holders of record on the relevant record date to receive interest due on the relevant interest payment date).

(d) The Notes may also be redeemed as set forth in Section 4.19 of the Indenture.

6. Mandatory Redemption. The Company shall not be required to make mandatory redemption or sinking fund payments with respect to the Notes.

7. Repurchase at Option of Holders.

(a) Unless the Company has previously or concurrently mailed a redemption notice with respect to all outstanding notes, upon the occurrence of a Change of Control, each Holder may require the Company to purchase such Holder’s Notes in whole or in part in amounts of $2,000 or whole multiples of $1,000 in excess thereof, at a purchase price in cash in an amount equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any, to the date of purchase, pursuant to a Change of Control Offer in accordance with the procedures set forth in the Indenture.

(b) Under certain circumstances described in the Indenture, the Company will be required to apply the proceeds of Asset Sales to the repayment of the Notes and/or Pari Passu Indebtedness.

8. Selection and Notice of Redemption. If less than all of the Notes are to be redeemed or purchased in an offer to purchase at any time, the Trustee shall select the Notes to be redeemed or purchased among the Holders of the Notes not more than 60 days prior to the redemption date in compliance with the requirements of the principal national securities exchange, if any, on which the Notes are listed or, if the Notes are not so listed, on a pro rata basis, by lot or in accordance with any other method the Trustee considers fair and reasonable (except that any Notes represented by a Global Note shall be selected by such method as the

Depositary or its nominee or successor may require or, where such nominee or successor is the trustee, a method that most nearly approximates pro rata selection as the trustee considers fair and appropriate). Redemptions pursuant to Section 3.07(b) of the Indenture shall be made on a pro rata basis or on as nearly a pro rata basis as practicable (except that any Notes represented by a Global Note will be selected by such method as the Depositary or its nominee or successor may require or, where such nominee or successor is the trustee, a method that most nearly approximates pro rata selection as the trustee deems fair and appropriate). In the event of partial redemption by lot, the particular Notes to be redeemed shall be selected, unless otherwise provided herein, not less than 30 nor more than 60 days prior to the redemption date by the Trustee from the outstanding Notes not previously called for redemption. Notices of redemption may not be conditional. If any Note is to be redeemed in part only, the notice of redemption that relates to that Note will state the portion of the principal amount thereof to be redeemed. A new Note in principal amount equal to the unredeemed portion of the original Note will be issued in the name of the Holder thereof upon cancellation of the original Note. Notes called for redemption become due on the date fixed for redemption. On and after the redemption date, interest, if any, shall cease to accrue on Notes or portions of them called for redemption.

9. Denominations, Transfer, Exchange. The Notes are in registered form without coupons in denominations of $2,000 and whole multiples of $1,000 in excess thereof. The transfer of Notes may be registered and Notes may be exchanged as provided in the Indenture. The Registrar and the Trustee may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and the Company may require a Holder to pay any taxes and fees required by law or permitted by the Indenture. The Company is not required to transfer or exchange any Note selected for redemption. Also, the Company is not required to transfer or exchange any Note for a period of 15 days before a selection of Notes to be redeemed.

10. Persons Deemed Owners. The registered Holder of a Note will be treated as its owner for all purposes.

11. Amendment, Supplement and Waiver. The Indenture or the Notes may be amended or supplemented only as provided in the Indenture.

12. Defaults. In the case of an Event of Default arising from certain events of bankruptcy, insolvency or reorganization specified in the Indenture, with respect to the Company or any Significant Subsidiary, all outstanding Notes will become due and payable immediately without further action or notice. If any other Event of Default occurs and is continuing, the Trustee or the Holders of at least 25% in principal amount of the then outstanding Notes may declare all unpaid principal of, premium, if any, and accrued interest on all Notes to be due and payable immediately, by a notice in writing to the Company (and to the Trustee if given by the Holders of the Notes) and upon any such declaration, such principal, premium, if any, and interest shall become due and payable immediately. The Trustee may withhold from Holders of the Notes notice of any continuing Default or Event of Default (except a Default or Event of Default relating to the payment of principal or interest) if it determines that withholding notice is in their interest. The Holders of not less than a majority in aggregate principal amount of the Notes outstanding by notice to the Trustee may on behalf of the Holders of all outstanding Notes waive any past Default and its consequences under the Indenture except a Default (1) in the payment of the principal of, premium, if any, or interest on any Note (which may only be waived with the consent of each Holder of Notes affected) or (2) in respect of a covenant or provision which under the Indenture cannot be modified or amended without the consent of the Holder of each Note affected by such modification or amendment.

13. Trustee Dealings with the Company. The Trustee, in its individual or any other capacity, may make loans to, accept deposits from, and perform services for the Company or its Affiliates, and may otherwise deal with the Company or its Affiliates, as if it were not the Trustee.

14. No Recourse Against Others. No director, officer, employee, member, limited partner or stockholder of the Company or any Restricted Subsidiary, as such, will have any liability for any obligations of the Company or the Restricted Subsidiaries under the Notes, the Indenture or the Guarantees to which they are a party, or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder of Notes by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for issuance of the Notes. The waiver may not be effective to waive liabilities under the federal securities laws.

15. Authentication. This Note shall not be valid until authenticated by the manual signature of the Trustee or an authenticating agent.

16. CUSIP Numbers. Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP numbers in notices of redemption as a convenience to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption and reliance may be placed only on the other identification numbers placed thereon.

17. Governing Law. This Note shall be governed by, and construed in accordance with, the laws of the State of New York.

The Company shall furnish to any Holder upon written request and without charge a copy of the Indenture. Requests may be made to:

RESOLUTE ENERGY CORPORATION

1675 Broadway

Suite 1950

Denver, Colorado 80202

Facsimile: 303 ###-###-####

Attention: General Counsel

ASSIGNMENT FORM

To assign this Note, fill in the form below:

to transfer this Note on the books of the Company. The agent may substitute another to act for him.

Date:                                                                                                                                                                                                                           

Signature Guarantee*:

OPTION OF HOLDER TO ELECT PURCHASE

If you want to elect to have this Note purchased by the Company pursuant to Section 4.11 or 4.19 of the Indenture, check the appropriate box below:

¨ Section 4.11             ¨ Section 4.19

If you want to elect to have only part of the Note purchased by the Company pursuant to Section 4.11 or Section 4.19 of the Indenture, state the amount you elect to have purchased:

$        

Date:                                         

SCHEDULE OF EXCHANGES OF INTERESTS IN THE GLOBAL NOTE

The following exchanges of a part of this Global Note for an interest in another Global Note or for a Definitive Note, or exchanges of a part of another Global Note or Definitive Note for an interest in this Global Note, have been made:

NOTATION OF GUARANTEE

For value received, each Guarantor (which term includes any successor Person under the Indenture) has, jointly and severally, fully and unconditionally and irrevocably guaranteed, to the extent set forth in the Indenture, dated as of April 25, 2012 (the “Indenture”), among Resolute Energy Corporation, a Delaware corporation (the “Company”), the Guarantors and U.S. Bank National Association, as trustee (the “Trustee”), and subject to the provisions in the Indenture, (a) the due and punctual payment of the principal of, premium, if any, and interest on the Notes (as defined in the Indenture), whether at maturity, by acceleration, redemption or otherwise, the due and punctual payment of interest on overdue principal and premium, and, to the extent permitted by law, interest, and the due and punctual performance of all other obligations of the Company to the Holders or the Trustee all in accordance with the terms of the Indenture and (b) in case of any extension of time of payment or renewal of any Notes or any of such other obligations, that the same will be promptly paid in full when due or performed in accordance with the terms of the extension or renewal, whether at stated maturity, by acceleration or otherwise. The obligations of the Guarantors to the Holders of Notes and to the Trustee pursuant to the Guarantee and the Indenture are expressly set forth in Article 10 of the Indenture and reference is hereby made to the Indenture for the precise terms of the Guarantee. This Guarantee shall be governed by and construed in accordance with the laws of the State of New York.