of mechanized suits called Vital Suits (VSs). VSs carry heavy weapons such as chainguns and rocket launchers. They can pick up weapons lying on the ground and fire multiple weapons at once. On foot, players are able to use a grappling hook to pull themselves up to normally hard-to-reach places, or to hook onto a VS and hijack it. Driving VSs and using certain weapons requires thermal energy. Also, the planet's cold temperature causes the characters' thermal energy level to continually decrease. Players can replenish their thermal energy level by defeating enemies or activating data posts. Data posts also allow players to use their navigational radars to see incoming enemies. Each of the 11 levels is accompanied by a boss, which can be either a VS or a large Akrid.