Within the caverns you will come across some coloured crystals, both inside and outside of buildings. These crystals are coloured to help you identify what crystal you are near, as each colour crystal has it's own function.

Here is information on what they do:

Armour Crystal

This crystal will replenish your armour at a slow rate when you are standing by it. Each armour type will take a different amount of time to replenish.

Health Crystal

This crystal will slowly replenish your health when you stand near to it. The Health crystal will start to replenish your health even if you are taking damage.

Vehicle Crystal

Park your vehicle near it to replenish the armour, a good place to park an AMS or any other vehicle. This crystal also works on aircraft if you fly next to it.

Weapons Crystal

Used to replenish AT weapon ammo when standing close to it. Useful to resupply yourself in the field, althouh this will not work with standard weapons.

Damage Crystal

A rare crystal that will damage you, thus taking health away from you, usually placed at the bottom of pits that you might get stuck in. The closer you are to it, the more damage it will do to you.