343 has revealed two new UNSC vehicles for Halo 4 - the hulking Mammoth troop carrier and a bipedal mech armed with rockets and cannons. Hey, who spilled Armored Core on my Halo? And who are those chaps with the rotting faces?
I'll tell you who the chaps with the rotten faces are, people. They're the Flood, and - PUT THE CHAIR DOWN. The Flood won't appear in single player, that we know of; their place has been taken by the new, incredibly dangerous and adaptable Promethean faction. They're just here for the multiplayer - specifically, for the Infection game type, which is now known, sensibly enough, as "Flood".
It supports 10 players, two of whom fill the fetid boots of highly contagious undead no-gooders, and the idea is to fight till all Flood forms are dead or everybody's caught the bug. Peruse screens of stinking corpses and the new rides below. There are 25 more where they came from.