Exhibit 10.4

ASSIGNMENT AND ASSUMPTION

OF

REGISTRATION RIGHTS AGREEMENT

This Assignment and Assumption of Registration Rights Agreement (this
“Assignment”) is entered into this 1st day of April, 2009, between Eldorado
Resorts LLC, a Nevada limited liability company (the “Assignor”), and Eldorado
HoldCo LLC, a Nevada limited liability company (the “Assignee”), and is
consented to by NGA AcquisitionCo, LLC a Nevada limited liability company
(“NGA”).

WHEREAS, Assignor and NGA are parties to that certain Registration Rights
Agreement dated December 14, 2007 (the “Agreement”), wherein NGA is granted
certain registration rights as more specifically set forth in the Agreement.

WHEREAS, the members of Assignor have contributed all their respective
membership interests in Assignor to Assignee in return for proportionate
membership interests in Assignee in accordance with that certain Contribution
Agreement of even date herewith.

WHEREAS, Assignor desires to assign all of its right, title and interest in the
Agreement to Assignee, and Assignee desires to assume all of Assignor’s duties,
obligations and liabilities in the Agreement, as more specifically set forth
herein.

NOW THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which is hereby acknowledged, Assignor hereby transfers to Assignee, and
Assignee hereby assumes, all of Assignor’s rights and obligations in the
Agreement as follows:

1. Assignment. Assignor assigns, transfers, sets over and delivers to Assignee
all of Assignor’s right, title and interest in, to and under the Agreement.

2. Assumption. Assignee assumes all duties, obligations and liabilities of
Assignor arising under the Agreement and agrees to comply with and fully perform
all of Assignor’s duties, obligations and covenants thereunder.

3. Consent. Subject to Section 2 above, NGA consents to Assignor’s assignment to
Assignee of its rights and obligations under the Agreement as set forth in this
Assignment.

4. Further Assurances. Assignor, Assignee and NGA will do, execute, acknowledge
and deliver all acts, assignments, transfers, notices and assurances as may be
reasonably required to evidence and perfect this Assignment.

5. Governing Law. This Assignment is governed by the laws of the State of
Nevada.

6. Binding Effect. This Assignment is binding upon and inures to the benefit of
Assignor, Assignee and NGA and their respective successors.

 

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7. Counterparts. This Assignment may be executed in any number of counterparts
and by facsimile signatures with the same effect as if all of the parties hereto
were to have physically signed the same document at the same time and at the
same place. All counterparts shall be construed together and shall constitute
the Assignment.

IN WITNESS WHEREOF, Assignor and Assignee have executed, and NGA has consented
to, this Assignment as of the day and year first set forth above.

 

Assignor:

   

Assignee:

Eldorado Resorts LLC, a

Nevada limited liability company

   

Eldorado HoldCo LLC, a

Nevada limited liability company

By:

 

/s/ Donald L. Carano

   

By:

 

/s/ Donald L. Carano

 

Donald L. Carano, Manager

     

Donald L. Carano, Manager

By:

 

/s/ Gary L. Carano

   

By:

 

/s/ Gary L. Carano

 

Gary L. Carano, Manager

     

Gary L. Carano, Manager

By:

 

/s/ Raymond J. Poncia, Jr.

   

By:

 

/s/ Raymond J. Poncia, Jr.

 

Raymond J. Poncia, Jr., Manager

     

Raymond J. Poncia, Jr., Manager

By:

 

/s/ Thomas Reeg

   

By:

 

/s/ Thomas Reeg

 

Thomas Reeg, Manager

     

Thomas Reeg, Manager

Consented To, Agreed And Accepted:

     

NGA AcquisitionCo, LLC, a

Nevada limited liability company

     

NGA AcquisitionCo, LLC, a Nevada limited liability company

     

By:

 

/s/ Tim Janszen

       

Tim Janszen, Manager

     

By:

 

/s/ Ryan Langdon

       

Ryan Langdon, Manager

     

By:

 

/s/ Roger May

       

Roger May, Manager

     

By:

 

/s/ Thomas Reeg

       

Thomas Reeg, Manager

     

 

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