AMENDMENT NUMBER TWO TO CREDIT AGREEMENT AND CONSENT

Exhibit 10.6

AMENDMENT NUMBER TWO TO CREDIT AGREEMENT AND CONSENT

This Amendment Number Two to Credit Agreement and Consent (“Amendment”) is entered into as of July 30, 2010, by and among the lenders identified on the signature pages hereof (such lenders, together with their respective successors and permitted assigns, are referred to hereinafter each individually as a “Lender” and collectively as the “Lenders”), and WELLS FARGO CAPITAL FINANCE, LLC, a Delaware limited liability company, as the agent for the Lenders (in such capacity, together with its successors and assigns in such capacity, “Agent”), on the one hand, and MAGMA DESIGN AUTOMATION, INC., a Delaware corporation (“Borrower”), on the other hand, with reference to the following facts:

A. Borrower, Agent, and Lenders have previously entered into that certain Credit Agreement, dated as of March 19, 2010 (as amended and modified, from time to time, the “Agreement”).

B. Borrower has requested that Agent and Lenders provide certain consents and make certain amendments to the Agreement as provided for and on the conditions set forth herein.

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby amend and supplement the Agreement as follows:

1. DEFINITIONS. All initially capitalized terms used in this Amendment shall have the meanings given to them in the Agreement unless specifically defined herein.

2. AMENDMENT. Clause (d) of Schedule 3.6 of the Agreement is hereby amended to read as follows:

“(d) To the extent any Inactive Subsidiary has not been dissolved within 60 days of the Closing Date (or by September 30, 2010 with respect to Aplus Design Technologies Inc.), Borrower shall (i) deliver to Agent all necessary documents to join such Inactive Subsidiary, as (x) a Guarantor under the Guaranty, (y) an Obligor under the Intercompany Subordination Agreement, and (z) a Grantor under the Security Agreement, and (ii) deliver to Agent the original certificates representing the shares of Stock pledged under the Security Agreement with respect to such Inactive Subsidiary, together with powers endorsed in blank with respect to such certificates.”

3. CONSENT. Borrower has informed Agent and Lenders that it intends to convert a portion of the outstanding 2014 Notes into the equity of Borrower (“Note Conversion”) and in order to induce certain holders of the 2014 Notes into the Note Conversion, Borrower has proposed to pay to each such noteholder an inducement fee (“Inducement Fee”). As the payment of the Inducement Fee is prohibited by the terms of the Agreement, Borrower has requested that Agent and Lenders consent thereto. Agent and Lenders hereby consent to the payment of the Inducement Fee so long as: (i) the amount of the Inducement Fee paid to the holders of the 2014 Notes does not exceed the aggregate amount of $3,500,000, (ii) the amount of the Inducement Fee paid to on any individual 2014 Note does not exceed 15% of the face value of such 2014 Note, (iii) immediately before the payment of any Inducement Fee no Default or Event of Default shall exist or shall occur as a result of the making of such payment, and (iv) the Note Conversion and payment of the Inducement Fee are completed by no later than September 30, 2010. This consent shall be effective only in this specific instance and for the specific purpose for which it is given, and shall not entitle Borrower to any other or further consent or waiver in any similar or other circumstances.

4. REPRESENTATIONS AND WARRANTIES. Borrower hereby affirms to Agent and Lenders that all of Borrower’s representations and warranties set forth in the Agreement are true, complete and accurate in all respects as of the date hereof.

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5. NO DEFAULTS. Borrower hereby affirms to Agent and Lenders that no Event of Default has occurred and is continuing as of the date hereof.

6. CONDITIONS PRECEDENT. The effectiveness of this Amendment is hereby conditioned upon receipt by Agent of (i) a fully executed copy of this Amendment from each party hereto and (ii) a fully executed copy of the attached Reaffirmation of General Continuing Guaranty.

7. REAFFIRMATION. Borrower hereby acknowledges and reaffirms (i) all of its obligations and duties under the Loan Documents, and (ii) that the Agent, for the ratable benefit of the Lender Group, has and shall continue to have valid, perfected Liens in the Collateral as provided in the Security Agreement.

8. COSTS AND EXPENSES. Borrower shall pay to Agent and Lenders all of Agent’s and Lenders’ out-of-pocket costs and expenses (including, without limitation, the fees and expenses of its counsel, which counsel may include any local counsel deemed necessary, search fees, filing and recording fees, documentation fees, appraisal fees, travel expenses, and other fees) arising in connection with the preparation, execution, and delivery of this Amendment and all related documents.

9. LIMITED EFFECT. In the event of a conflict between the terms and provisions of this Amendment and the terms and provisions of the Agreement, the terms and provisions of this Amendment shall govern. In all other respects, the Agreement, as amended and supplemented hereby, shall remain in full force and effect.

10. COUNTERPARTS; EFFECTIVENESS. This Amendment may be executed in any number of counterparts and by different parties on separate counterparts, each of which when so executed and delivered shall be deemed to be an original. All such counterparts, taken together, shall constitute but one and the same Amendment. This Amendment shall become effective upon the execution of a counterpart of this Amendment by each of the parties hereto. This Amendment is a Loan Document and is subject to all the terms and conditions, and entitled to all the protections, applicable to Loan Documents generally.

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IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of the date first set forth above.

Amendment Number Two to Credit Agreement and Consent

Amendment Number Two to Credit Agreement and Consent

REAFFIRMATION OF GENERAL CONTINUING GUARANTY

Dated as of July 30, 2010

The undersigned (the “Guarantor”), has executed a General Continuing Guaranty, dated as of March 19, 2010 (the “Guaranty”), in favor of Wells Fargo Capital Finance, LLC (“Agent”), respecting the obligations of Magma Design Automation, Inc., a Delaware corporation (“Borrower”) pursuant to that certain Credit Agreement dated as of March 19, 2010 by and between Borrower, the Lenders signatory thereto and Agent, and other Loan Documents. Guarantor acknowledges the terms of the above Amendment and reaffirms and agrees that: (a) its Guaranty remains in full force and effect; (b) nothing in the Guaranty obligates Agent to notify the undersigned of any changes in the loans and financial accommodations made available to Borrower or to seek reaffirmation of the Guaranty; and (c) no requirement to so notify any of the undersigned or to seek reaffirmation in the future shall be implied by the execution of this reaffirmation.

Reaffirmation of General Continuing Guaranty