The M3 Crocodile is a amphibious infantry fighting vehicle used by the UNSC for frontline infantry transport, with sufficient armour and weapon systems to provide a suitable firebase for the embarked infantry units. Later in the war, the Crocodile was upgraded with a 30mm rail gun capable of high rates of fire. This, mixed with explosive and armour piercing rounds availible for it increased its lethality against both soft and hard targets, such as infantry, armour and structures.