And starting at ~1:40 into the video (with thanks to BryanNewman for the heads-up), Project HRUNTING/YGGDRASIL, which some might remember from the anime episode "Prototype" from Halo Legends:

Click here for full-sized version.

If indeed the suit from Prototype is going to be shown off in HW2, I will be interested to see if they just severely nerfed it (I hope not: that would be lame, and would defeat the point of letting something of that caliber show up in the first place, IMO), or if they went a cooler route and just made it something like a command power or something, where it shows up, wrecks things, and then leaves, either once all ammo is expended, its timer runs down, or it's destroyed.