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.

Note: The Ragnarok mech is a perfect blend of armor, firepower, and heat design as long you do not use the lava gun constantly. The Ymir has greater firepower than the regular chassis of Ragnarok. However, it generates a great deal more heat, making it a good choice for advanced players for to make short work of their opposition.