Shields are a gameplay element in Marathon. They serve as the player's health, and if fully depleted the player dies. Shields are depleted by being hit by attacks, being crushed against a wall by a moving platform, and standing in lava, Pfhor slime, and plasma. Shields have three levels levels of charge, each represented by a different color to allow players to know how much shields they have, despite each level of shielding taking up the same space in the shield bar. 1x shields are red, 2x are yellow, and 3x are purple. Players spawn with a full level of 1x shields. Shields can be recharged at shield recharging stations, which are used like switches: walk up to them, and press the action key. If you look around or move around the shield recharging will stop, so stay still while recharging. There are three types of recharge terminals, each able to fill your shields up to a maximum of one of the levels of shields, e.g., one terminal can completely fill up the level of 1x shields, one can comepletely fill up the levels of 1x and 2x shields, and one can fill up all three levels.