Microsoft has announced the second official expansion pack to its sci-fi-themed simulation MechWarrior 4: Vengeance. Designed by Cyberlore Studios, the company responsible for last year's MechWarrior 4: Black Knight expansion pack, the Inner Sphere 'Mech Pak is designed to broaden the core gameplay of MechWarrior 4. It will introduce of a number of new mechs, a couple of new gadgets to equip them with, and a new "coliseum" multiplayer mode that pits two mech pilots against each other at a time while others look on.

　　The Inner Sphere 'Mech Pak was designed by committee--its four new mechs were actually selected based on a survey of fans Microsoft conducted earlier this year. The four new Inner Sphere mechs that will be featured in the expansion are popular standbys from FASA's BattleTech pen-and-paper game, the source material for MechWarrior 4. These include the hunchback, a medium-weight powerhouse; the dragon, a swift but powerful strike mech; the highlander, a gigantic assault mech equipped with jump jets; and the zeus, an imposing ranged-attack mech.

　　The MechWarrior 4 Inner Sphere 'Mech Pak is scheduled to ship in the spring for an estimated retail price of $9.95. That's a fraction of the price of the $29 Black Knight expansion pack, though the Inner Sphere 'Mech Pak seems to have less content in it. For instance, Microsoft has not revealed whether the new expansion will have any new single-player missions. Stay tuned for further details on this forthcoming add-on.