Crystal Core is the main Crystal Space demo game. It makes heavy use of CEL and CELstart. It is going to be a first person shooter with many quest and puzzle elements. The three main purposes of Crystal Core are:

• Be a good and playable game.
• Be a good tutorial on how to make games using Crystal Space, CEL, and CELstart.
• Spawn a modding community. Crystal Core is heavily modular and extensible.

Check out the developers site for more information about the game.