The Inner Sphere Mech Pak adds new BattleMechs and new technology compatible with MechWarrior 4: Vengeance and with the MechWarrior 4: Black Knight expansion.Those additions include four new Mechs:

· Zeus – A classic Inner Sphere design, the Zeus is an extremely reliable long-range Assault 'Mech

· Highlander - A massive jump-capable Assault 'Mech and signature 'Mech of the Northwind Highlanders mercenary unit

· Hunchback - Easily identified by its oversized auto-cannon, the Hunchback is a tough brawler armed for short-range combat

· Dragon - A speedy all-around frontline striker and a favored Mech of House Kurita commanders