First of all, we will be launching an Editor for Crysis 2 early in summer. This will allow you to build new maps, items, gameplay modes and more custom content for Crysis 2. For teams looking for even more creative freedom, we have another option: The free CRYENGINE SDK.
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In August 2011 we will be launching a free CryENGINE SDK. If you want to use it for fun, like all our previous MOD SDKs it will be completely free of charge, to anyone who wants to play with it! You just register, download the SDK with a personalized license key and you're good to go!
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This will be a complete version of our engine, including C++ code access, our content exporters (including our LiveCreate real-time pipeline), shader code, game sample code from Crysis 2, script samples, new improved Flowgraph and a whole host of great asset examples, which will allow teams to build complete games from scratch for PC.