Hey,
there are 2 cd keys, what is the differences?

And I weer is my Multiplayer bonus?

Purchase Crysis 2 before March 26th and receive a free upgrade to the Limited Edition!
(see offer restriction below)

Limited Edition includes the following Multiplayer bonus content:

Hologram Decoy

SCAR weapon attachment
Project a hologram of yourself used to deceive and confuse enemies

SCAR weapon skin – digital

Medium assault rifle
High accuracy and fire rate
Unique digital camouflage variant

Unique Platinum Dog Tag

Displays your rank
Can be viewed by others
Helps identify players
Unique platinum frame not available through any other means

Bonus XP

Awards additional experience
Immediate boost to level 5
Immediate access to all preset classes

??

and the single player is awesome ty crytek staff for the best game of there year!