The Spartan Assault Tank was designed by the Mechanicum of Mars for the Space Marine Legions as a way to carry their Terminators into combat. This was because the Land Raider Proteus, the only Land Raider the Space Marine Legions had access to early in the Great Crusade, was unable to carry the bulk of Terminators and a way to carry these highly-effective warriors quickly into combat was needed. One tale says that the Spartan was designed specifically so that an Astartes strike force could cross a region ablaze with raging plasma fires, referred to as the Ring of Death. The Space Marines amassed their Terminators and used the first Spartans to carry them across this region, losing all but a fraction of the Terminator Squads. The sacrifice proved not in vain though as the battle was eventua