Mk. II Grizzly Tank Destroyer

Although the original Grizzly Main Battle Tanks first took to the field of battle on Harvest, they would see extensive use in other combat theatres as well. Though expensive, their superior firepower, flexibility and armour made them perfect against Covenant armoured forces. The Mark I would continue service until the end of the war, becoming a favourite among the UNSC Army and Marine Corps.

The Mark II Grizzly was concieved with a much more sapecific role in mind - a dedicated tank killer. The addition of two advanced railguns to replace the high velocity cannons originally mounted, the removal of the M247 GPMG, and various alterations to the vehicle's configuration and external hull meant that, while it shared the overall outline of the original Grizzly, it was a radically different machine.

Quotes

 * "I remember at Sydney, we had an enemy armoured column advancing on us - Ghosts harrassing our flanks, Wraiths shelling the shit out of us. Next thing we know, there's a bunch of bangs and flashes, and the enemy is running for it's life! And that was just one tank!"
 * "They were never made in really significant numbers. You'd occasionally see one on the battlefield, but the vast majority were destroyed in the initial bombardment."
 * "It really needs a machinegun, though. It may be an excellent tank killer, but it's pretty crap against infantry, and needs a fireteam on the treads for that kind of protection. I was a Brute just charge up to it, dodging railgun fire, and stick a spike 'nade to the hull - we shot the bastard full of lead and dived off, but the track was shot. We had to abandon the tank."
 * "I prefer the Mark I. It's cannons aren't as powerful, but it's a lot more flexible than the Mark II. It's good against anything - infantry, armour, aircraft, you name it. I'd definitely rather have this think further back, laying down fire from far, far away, than have it rolling past me."