Crystal Caves

Z+E+U+S (God Mode: With God Mode on, G will toggle gravity)

N+E+X+T (Warp Mode)

X+T+R+A (Increase Ammo)

Note: For "Warp Mode" and "Increase Ammo" you must release the third key of the four-key combination before you release the other keys.

Example:

Warp Mode:

First, press and hold: N E X T

Next, release: X

Then, release the other three keys.