2 Player UFO v. Farmers

This game belongs to video 

As such, it is a 2 player game. But, you can play it alone too!

It should either be played with 2 keyboards (if that works?) or on an arcade like I have. Of course, you can play it alone and just let the other player die :D

CONTROLS

PLAYER 1
WASD: MOVE
ARROWS: SHOOT

PLAYER 2
IJKL: MOVE
KEYPAD 8456: SHOOT