The game engine is a basic thing? Did you even think before you typed that? Seriously... That's the core of the game dude... The games are nothing alike beside the fact they are both futuristic.. I didn't enjoy advanced warfare much, I enjoy bo3 more than any cod in the past 3 or 4 years.. Great game. Honestly all that matters is the person who is playing the game likes it and enjoys it, that's it bottom line. Btw ign gave bo3 a 9.2/10