Here are some cheats and tips for the game Mech Assault.
Completion bonuses:
Successfully complete the game to unlock Ragnarok in
local multi-player mode.
Successfully complete the game under any difficult
setting to unlock a mech called Ymir.
Easy Last Man Standing win:
Get at least three players. Hide, and then after everyone has
killed the others, come back out and fight the last player
that was standing.