When you open the game, and the intro ends, enter the Konami code:
⇧ ⇧ ⇩ ⇩ ⇦ ⇨ ⇦ ⇨ B A and Enter. (Works on keyboard an controller too. NOT WASD, ARROWS!)
If you did it well, you see this.
after pressing enter you see this

now you finally know how to unlock the MOAI