The Pelican Dropship is the primary ground-troop and supply deployment vehicle. Able to enter and leave the atmosphere of most planets several times, the Pelican can carry a Warthog or a Scorpion Tank, as well as a fully supplied squad of Marines. Used for reconnasince and landings, the Pelican can carry enough troops and supplies to fully secure a landing zone in the first drop.

 In the original Halo, Master Chief and Cortana escaped from Halo on a Longsword Fighter. At E3 when they showcased the HALO 2 video the Longsword was seen bombing the huge Covenant Plasma Artillery into bits and pieces.

Although the Longsword is not directly used in Halo 2 by the Master Chief, it is a major part of the defense of Earth against the Covenant Invasion, used to relay bombing runs against Covenant positions and provide cover for advancing Marines.  

M12 Warthog LAV

The M12 is the standard Human ground vehicle. Able to carry three soldiers, the Warthog is great on all terrain, due to good traction and some tweaks in the brakes. Equiped with a three-barreled 12.7 MM LAAG Machine Gun, this vehicle is a force to be reckoned with on the battlefield. Another variant of the M12 is the M1261 LAAV, which is completly the same exept for the 25 MM Gauss Cannon in replacement of the LAAG.

 M808B Scorpion MBT

A Scorpion rolling over a hill is a heart-attack inducing sight on the battlefield, as this machine is liable to kill anything that opposes it. Although it's primary role is to demolish opposing vehicles with it's 90MM high-velocity shell, it can just as easily cut through ranks of opponents with the 7.62MM armor-piercing tracer rounds that fly from it's machine-gun. Almost invincible to small-arms, the only things that can effectivly stop this tank are rockets, plasma cannons/shells, machine-gun turrets, and well-placed grenades. One driver, although passengers can sit on the 4 side jumpseats. Note-In multiplayer, you cannot use the jumpseats, so you can stand on the tank, instead.