CGF file extension usually associated with CryEngine software files, it is a 3d game engine which used 3D application CryEngine SDK.  

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In this article, we will discuss different ways we can open a cgf file. Silky Terrier Dog Breed Playing Around

Method#1 Online CGF viewer  

• File-Extension (www.file-extensions.org)
• Open CGF file 

It provides two ways through which we can opened a CGF file, you can opened either in text editor or in the config.app  

Method#2 Through Application 

• Crytek cryENGINE SDK 

It’s available in paid version but free trial period is also available