-multiplayer
all games should have a multiplayer mode or a split screen or co-op something
-A lot of weapons/moves/parts etc
this depends of the type of the game but lets say you have a racing game it should have lots of parts to upgrade the look and preformance of your car or an rpg should have lots of weapons/iteams/guns etc etc...same goes for an fps lots of different guns.
anything else to add? reply