Exhibit 10.2

VOTING AGREEMENT

This Voting Agreement (this “Agreement”) is dated as of April 20, 2006, by and
among Petrohawk Energy Corporation (“Petrohawk”), KCS Energy, Inc., a Delaware
corporation (“KCSR”), and                      (the “Stockholder”).

WHEREAS, Stockholder desires that Petrohawk, Hawk Nest Corporation, a Delaware
corporation and wholly-owned subsidiary of Petrohawk (“Purchaser”), and KCS
enter into the Agreement and Plan of Merger dated the date hereof (the “Merger
Agreement”; undefined capitalized terms herein are defined in the Merger
Agreement) providing for the merger of Purchaser with and into KCS and for the
merger of KCS with and into Parent (the “Merger”) upon the terms and subject to
the conditions set forth in the Merger Agreement;

WHEREAS, Stockholder is executing this Agreement as an inducement to Petrohawk
to enter into and execute the Merger Agreement (and this Agreement shall not be
effective until the parties to the Merger Agreement execute the Merger
Agreement); and

WHEREAS, the Board of Directors of KCS has adopted such resolutions as are
necessary so that the provisions of Section 203 of the DGCL are inapplicable to
the execution and performance of this Agreement;

NOW, THEREFORE, in consideration of the execution and delivery by Petrohawk of
the Merger Agreement and the mutual covenants, conditions and agreements
contained herein and therein, the parties agree as follows:

1. Representations and Warranties.

(a) Stockholder represents and warrants to Petrohawk as follows:

(i) Stockholder is the record and beneficial owner of that number of shares of
capital stock of KCS set forth opposite its name on Schedule A (together with
any other shares of other capital stock of KCS acquired after the date hereof,
including through the exercise of any stock options, warrants or similar
instruments, being collectively referred to herein as the “Subject Shares”) and
the other securities exercisable or exchangeable for such capital stock listed
on Schedule A (the “Other Securities” and, together with the Subject Shares, the
“Covered Securities”). Stockholder has the sole right to vote and Transfer (as
defined herein) the Covered Securities set forth opposite its name on Schedule
A, and none of such Covered Securities is subject to any voting trust or other
agreement, arrangement or restriction with respect to the voting or the Transfer
of the Subject Shares, except (A) as provided by this Agreement (it being
understood that any pledge of the Pledged Shares (as defined below) shall not be
a breach of this representation), (B) those arising under applicable securities
laws and (C) Stockholder shall be entitled to vote the Subject Shares with
respect to the election of directors at KCS’s annual meeting of stockholders to
be held on May 25, 2006 (the “Annual Meeting”). Stockholder has all requisite
power and authority, and the legal capacity, to enter into this Agreement and to
perform its obligations hereunder. This Agreement has been duly executed and
delivered by, and constitutes a valid and binding agreement of, Stockholder,
enforceable against Stockholder in accordance with its terms, except as

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enforcement may be limited by or subject to the effects of bankruptcy,
insolvency, reorganization, moratorium and other laws relating to or affecting
the rights of creditors and of general principles of equity.

(ii) Neither the execution and delivery of this Agreement nor the performance by
Stockholder of its obligations hereunder will result in a violation of, or a
default under, or conflict with any contract, trust, commitment, agreement,
understanding, arrangement or restriction of any kind (other than as may relate
to the Pledged Shares but subject to the proviso set forth in (iv) below) to
which Stockholder is a party or bound or to which the Covered Securities are
subject, except as would not prevent, delay or otherwise materially impair
Stockholder’s ability to perform its obligations hereunder. Execution, delivery
and performance of this Agreement by Stockholder will not violate, or require
any consent, approval or notice under, any provision of any judgment, order,
decree, statute, law, rule or regulation applicable to Stockholder or the
Covered Securities, except (x) for any reports under Sections 13(d) of the
Exchange Act as may be required in connection with this Agreement and the
transactions contemplated hereby or (y) as would not reasonably be expected to
prevent, delay or otherwise materially impair Stockholder’s ability to perform
its obligations hereunder.

(iii) If Stockholder is married and the Covered Securities of Stockholder
constitute community property or spousal approval is otherwise required for this
Agreement to be legal, valid and binding, then, to the extent so required, this
Agreement has been duly authorized, executed and delivered by, and constitutes a
valid and binding agreement of, Stockholder’s spouse, enforceable against such
spouse in accordance with its terms, subject to the effects of bankruptcy,
insolvency, reorganization, moratorium and other laws relating to or affecting
the rights of creditors and of general principles of equity.

(iv) The Covered Securities and the certificates representing such Covered
Securities are held by Stockholder, or by a nominee or custodian for the benefit
of Stockholder, free and clear of all liens, claims, security interests,
proxies, voting trusts or agreements, understandings or arrangements or any
other encumbrances whatsoever, except for (A) any such encumbrances arising
hereunder, (B) Stockholder may vote the Subject Shares in connection with the
election of directors at the Annual Meeting, or (C) any such encumbrances
arising pursuant to the pledge of any Covered Securities by Stockholder to a
financial institution or a brokerage firm (the “Pledged Shares”); provided,
however, that Stockholder represents that any such arrangement regarding such
Pledged Shares shall not prevent, delay or otherwise materially impair
Stockholder’s ability to execute and deliver this Agreement or perform its
obligations hereunder, and Stockholder shall use its reasonable efforts to
obtain an acknowledgment by the pledgee of the terms of this Agreement and such
pledgee’s agreement to vote the Pledged Shares (if and to the extent the voting
power of the Pledged Shares is being or to be exercised by pledgee) in
accordance with Section 2.

(v) Except as disclosed in the Merger Agreement, no broker, investment banker,
financial advisor or other person is entitled to any broker’s, finder’s,
financial advisor’s or other similar fee or commissions based upon arrangements
made by or on

 

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behalf of Stockholder in connection with its entering into this Agreement.
Stockholder shall have no obligation or liability of any kind with respect to
any fee, commissions or other amount of any kind incurred or payable by or on
behalf of Petrohawk or KCS in connection with the Merger.

(vi) Stockholder understands and acknowledges that Petrohawk is entering into
the Merger Agreement in reliance upon Stockholder’s execution and delivery of
this Agreement. KCS and Petrohawk understand and acknowledge that Stockholder is
entering into this Agreement in reliance upon Petrohawk’s and KCS’s execution
and delivery of the Merger Agreement and intended consummation of the Merger.

(b) Petrohawk represents and warrants to Stockholder and KCS that:

(i) The execution and delivery of this Agreement and the Merger Agreement (the
“Transaction Documents”) by Petrohawk and the performance by Petrohawk of its
obligations thereunder and the consummation of the transactions contemplated
thereby have been duly authorized by all necessary action on the part of
Petrohawk. Each of the Transaction Documents has been duly executed and
delivered by, and constitutes a valid and binding agreement of, Petrohawk,
enforceable against Petrohawk in accordance with its terms, except as
enforcement may be limited by or subject to the effects of bankruptcy,
insolvency, reorganization, moratorium and other laws relating to or affecting
the rights of creditors and of general principles of equity.

(ii) Neither the execution and delivery of the Transaction Documents nor the
performance by Petrohawk of its obligations thereunder will result in a
violation of, or a default under, or conflict with, (A) any provision of its
certificate of incorporation, bylaws, partnership agreement, limited liability
company agreement or similar organizational documents, (B) any contract, trust,
commitment, agreement, understanding, arrangement or restriction of any kind to
which Petrohawk is a party or bound, except, in the case of clause (B), as would
not prevent, delay or otherwise materially impair Petrohawk’s ability to perform
its obligations thereunder or consummate the Merger. Execution, delivery and
performance of the Transaction Documents by Petrohawk will not violate, or
require any consent, approval or notice under, any provision of any judgment,
order, decree, statute, law, rule or regulation applicable to Petrohawk or the
Covered Securities, except (x) for any reports under Sections 13(d) of the
Exchange Act as may be required in connection with this Agreement and the
transactions contemplated hereby or (y) as would not reasonably be expected to
prevent, delay or otherwise materially impair Petrohawk’s ability to perform its
obligations thereunder or consummate the Merger.

(iii) There is no action, claim, suit, demand, hearing, notice of violation or
deficiency, or proceeding (including any investigation or partial proceeding,
such as a deposition), domestic or foreign, pending, or to the knowledge of
Petrohawk threatened, that could prevent the consummation of, materially impair
or materially delay the Merger or any of the transactions contemplated hereby.

 

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(c) KCS represents and warrants to Stockholder and Petrohawk that:

(i) The execution and delivery of the Transaction Documents by KCS and the
performance by KCS of its obligations thereunder and consummation of the
transactions contemplated thereby have been duly authorized by all necessary
action on the part of KCS. Each of the Transaction Documents has been duly
executed and delivered by, and constitutes a valid and binding agreement of,
KCS, enforceable against KCS in accordance with its terms, except as enforcement
may be limited by or subject to the effects of bankruptcy, insolvency,
reorganization, moratorium and other laws relating to or affecting the rights of
creditors and of general principles of equity.

(ii) Neither the execution and delivery of the Transaction Documents nor the
performance by KCS of its obligations thereunder will result in a violation of,
or a default under, or conflict with, (A) any provision of its certificate of
incorporation or bylaws, (B) any contract, agreement or other legally binding
instrument or obligation to which KCS is a party or bound, except in the case of
clause (B), as would not be reasonably likely to have or result in a Material
Adverse Effect on the Company or prevent or delay or otherwise materially impair
KCS’s ability to perform its obligations thereunder or consummate the Merger.
Execution, delivery and performance of the Transaction Documents by KCS will not
violate or conflict with any provision of any judgment, order, decree, statute,
law, rule or regulation applicable to KCS or the Covered Securities, except
(x) for any reports under Sections 13(d) of the Exchange Act as may be required
in connection with this Agreement and the transactions contemplated hereby or
(y) as would not be reasonably likely to have or result in a Material Adverse
Effect on the Company or would not be reasonably likely to prevent, delay or
otherwise materially impair KCS’s ability to perform its obligations thereunder
or consummate the Merger.

(iii) There is no Litigation pending, or to the Knowledge of KCS, threatened
that would prevent the consummation of, materially impair or materially delay
the Merger or any of the transactions contemplated hereby.

(d) Petrohawk and KCS each represent and warrant to Stockholder that:

(i) Other than the voting agreements of even date herewith between Petrohawk,
KCS and the persons identified on Schedule B (the “Other Support Agreements”),
Stockholder and others, a form of which agreements are, or will be, publicly
filed, it is not a party to any agreement or understanding with any stockholder
with respect to shares of capital stock of KCS.

(ii) The Other Support Agreements contain terms and conditions substantially the
same as and no more or less favorable to any other stockholder party thereto
than those contained in this Agreement.

(iii) Entering into this Agreement and the Other Support Agreements shall not
result in any adverse consequence to the Stockholder under Section 203 of the
DGCL, or any similar protective provisions of the DGCL.

(iv) To our Knowledge, no filings of any kind (other than a Schedule 13D under
the Exchange Act reflecting this Agreement and any such Other Support

 

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Agreement) shall be required to be filed by Stockholder or any such other
stockholders in connection with the entering into of this Agreement or the Other
Support Agreements or the consummation of the Merger, including, without
limitation, any Section 16 filings under the Exchange Act.

2. Voting Agreements. During the Term (as defined below) of this Agreement, at
any meeting of stockholders of KCS or at any adjournment thereof or in any other
circumstances upon which a vote, consent or other approval (including by written
consent) relating to the Merger is sought, Stockholder shall, including by
executing a written consent solicitation if requested by Petrohawk, vote (or
cause to be voted) the Subject Shares: (a) in favor of the Merger, the adoption
by KCS of the Merger Agreement and the approval of the terms thereof and each of
the other transactions contemplated by the Merger and (b) against any
transaction, agreement, matter or other Acquisition Proposal that would
reasonably be expected to impede, interfere with, delay, postpone or attempt to
discourage the Merger and the Merger Agreement.

3. Irrevocable Proxy. Stockholder hereby appoints Petrohawk as its proxy to vote
all of the Stockholder’s Subject Shares at any meeting of stockholders of KCS
(including any adjournments and postponements thereof) on the matters described
in Section 2, and to execute and deliver any written consents to fulfill such
Stockholder’s obligations under this Agreement. This proxy is coupled with an
interest and is irrevocable until the end of the Term, at which time it shall
terminate.

4. Revocation of Other Proxies. To the extent inconsistent with the other
provisions of this Agreement or the Merger Agreement, Stockholder hereby revokes
any and all previous proxies with respect to the Subject Shares.

5. Other Covenants. Stockholder agrees with, and covenants to, Petrohawk during
the Term of this Agreement as follows:

 

  (a) Stockholder shall not after the date hereof (i) sell, transfer, pledge,
assign or otherwise dispose of (including by gift) (collectively, “Transfer”),
or consent to any Transfer of, any Covered Securities or any interest therein,
except pursuant to the Merger, (ii) enter into any contract, option or other
agreement with respect to any Transfer of any or all of the Covered Securities
or any interest therein, (iii) grant any proxy, power-of-attorney or other
authorization in or with respect to the Subject Shares (except it is recognized
that Stockholder may vote the Subject Shares in connection with the election of
directors at the Annual Meeting) or (iv) deposit the Subject Shares into a
voting trust or enter into a voting agreement or voting arrangement with respect
to the Subject Shares; provided, that Stockholder may Transfer any of the
Covered Securities to an affiliate of Stockholder or pursuant to any bona fide
charitable gift or by will or applicable laws of descent and distribution, or
for estate planning purposes (provided such transferee evidences in a writing
reasonably satisfactory to the other parties hereto such transferee’s agreement
to the terms hereof) or any other person or entity who is on the date hereof or
hereafter becomes a party to a similar agreement; provided, further, that the
restrictions in this Section 5 shall not be deemed violated by any Transfer of
Covered Securities pursuant to a cashless exercise of stock options or warrants;
and provided, further, that a pledge of Pledged Shares made in accordance with
Section 1(a)(iv) shall not be deemed to be a violation of the restrictions in
this Section 5.

 

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(b) Stockholder hereby waives any rights of appraisal, or rights to dissent from
the Merger, that such Stockholder may have.

6. Certain Events. This Agreement and the obligations hereunder shall, during
the Term hereof, attach to Stockholder’s Covered Securities and shall be binding
upon any Person to which legal or beneficial ownership of such Shares shall
pass, whether by operation of law or otherwise, including Stockholder’s
administrators or successors. In the event of any stock split, stock dividend,
merger, reorganization, recapitalization or other change in the capital
structure of KCS affecting the Covered Securities or the acquisition of
additional shares of Covered Securities or other voting securities of KCS by
Stockholder, the number of Covered Securities listed on Schedule A beside the
name of Stockholder shall be adjusted appropriately, and this Agreement and the
obligations hereunder shall attach to any additional Covered Securities or other
voting securities of KCS issued to or acquired by Stockholder.

7. Stop Transfer. KCS shall not register the transfer of any certificate
representing any Covered Securities during the Term hereof, unless such transfer
is made to Petrohawk or otherwise in compliance with this Agreement.

8. Stockholder Capacity. No person executing this Agreement (or an affiliate
thereof) who is or becomes during the Term a director of KCS makes any agreement
or understanding herein in his capacity as such director. Stockholder signs
solely in its capacity as the record and beneficial owner of, or the trustee of
a trust whose beneficiaries are the beneficial owners of, Stockholder’s Covered
Securities.

9. Further Assurances. Stockholder shall, upon request of Petrohawk, execute and
deliver any additional documents and take such further actions as may reasonably
be deemed by Petrohawk to be necessary or desirable to carry out the provisions
hereof.

10. Termination. This Agreement, and all rights and obligations of the parties
hereunder, shall commence upon the execution of the Merger Agreement as
contemplated above and terminate upon (and shall only be effective from the date
hereof until) the first to occur of (i) the Effective Time, (ii) the date upon
which the Merger Agreement is terminated in accordance with its terms, (iii) the
mutual consent of Petrohawk and Stockholder, (iv) the date of any amendment,
waiver or modification to the Merger Agreement in a manner that reduces the
Merger Consideration or otherwise materially adversely affects the Stockholder,
or (v) December 31, 2006 (such period from the date hereof until such
termination is referred to herein as the “Term”)

11. Miscellaneous.

(a) All notices, requests, claims, demands and other communications under this
Agreement shall be in writing and shall be deemed given if delivered personally
or sent by overnight courier (providing proof of delivery) to the parties at the
following addresses (or at such other address for a party as shall be specified
by like notice): (i) if to Petrohawk or KCS, to the appropriate address set
forth in Section 8.4 of the Merger Agreement; and (ii) if to Stockholder, to the
appropriate address set forth on Schedule A.

 

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(b) Each party to this Agreement (“Party”) submits to the jurisdiction of any
state or federal court sitting in the State of Delaware in any dispute or action
arising out of or relating to this Agreement and agrees that all claims in
respect of such dispute or action may be heard and determined in any such court.
Each Party also agrees not to bring any dispute or action arising out of or
relating to this Agreement in any other court. Each Party agrees that a final
judgment in any dispute or action so brought will be conclusive and may be
enforced by action on the judgment or in any other manner provided at law
(common, statutory or other) or in equity. Each Party waives any defense of
inconvenient forum to the maintenance of any dispute or action so brought and
waives any bond, surety, or other security that might be required of any other
Party with respect thereto.

(c) The headings contained in this Agreement are for reference purposes only and
shall not affect in any way the meaning or interpretation of this Agreement.

(d) This Agreement may be executed in two or more counterparts, all of which
shall be considered one and the same agreement and shall become effective as to
Stockholder when one or more counterparts have been signed by each of Petrohawk,
KCS and Stockholder and delivered to Petrohawk, KCS and Stockholder.

(e) Other than the Merger Agreement and the Confidentiality Agreement, this
Agreement (including the documents and instruments referred to herein)
constitutes the entire agreement, and supersedes all prior agreements and
understandings, both written and oral, among the parties with respect to the
subject matter hereof, and this Agreement is not intended to confer upon any
other person (other than Purchaser) any rights or remedies hereunder.

(f) This Agreement shall be governed by, construed and enforced in accordance
with, the laws of the State of Delaware, without giving effect to the principles
of conflicts of laws thereof.

(g) Neither this Agreement nor any of the rights, interests or obligations under
this Agreement shall be assigned, in whole or in part, by operation of law or
otherwise, by any of the parties without the prior written consent of the other
parties, except that Stockholder may transfer Covered Securities to the extent
permitted by Section 5(a) of this Agreement. Any assignment in violation of the
foregoing shall be void.

(h) As between Stockholder and Petrohawk, each of such Parties agrees that
irreparable damage to the other, non-breaching party would occur and that such
non-breaching party would not have any adequate remedy at law in the event that
any of the provisions of this Agreement were not performed in accordance with
their specific terms or were otherwise breached. It is accordingly agreed that
the non-breaching party shall be entitled to an injunction or injunctions to
prevent breaches by the other party of this Agreement and to enforce
specifically the terms and provisions of this Agreement, this being in addition
to any other remedy to which it may be entitled at law or in equity.

 

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(i) If any term, provision, covenant or restriction herein, or the application
thereof to any circumstance, shall, to any extent, be held by a court of
competent jurisdiction to be invalid, void or unenforceable, the remainder of
the terms, provisions, covenants and restrictions herein and the application
thereof to any other circumstances shall remain in full force and effect, shall
not in any way be affected, impaired or invalidated, and shall be enforced to
the fullest extent permitted by law.

(j) No amendment, modification or waiver in respect of this Agreement shall be
effective against any Party unless it shall be in writing and signed by such
Party.

[SIGNATURE PAGE FOLLOWS]

 

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IN WITNESS WHEREOF, Petrohawk, KCS, and the Stockholder have caused this
Agreement to be duly executed and delivered as of the date first written above.

 

Petrohawk Energy Corporation By:  

 

Name:   Floyd C. Wilson Title:   Chairman, President and Chief Executive Officer
KCS Energy, Inc. By:  

 

Name:   James W. Christmas Title:   Chairman, President and Chief Executive
Officer STOCKHOLDER:

 

 

STOCKHOLDER SPOUSE:

 

 

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SCHEDULE A

 

NAME AND ADDRESS

  

NUMBER

OF SHARES

  

NUMBER

OF OPTIONS,
WARRANTS, ETC.

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SCHEDULE B

James W. Christmas

William N. Hahne

Harry Lee Stout

Joseph T. Leary