Blue_Stuff said: As someone who's never seen Gundam, can someone explain what that thing is?
Primarily, this is the Devil Gundam (Dark Gundam, in English) from the G Gundam universe. It was outfitted with nanotechnology for the purposes of restoring Earth from the damage caused by the Gundam fights of the said series. It was separated from its creator, crashed to Earth, and malfunctioned, leading it down a path whereby it would attempt to destroy humanity. Nanomachines.
The Reborns Gundam is the personal mobile suit piloted by the big bad of Gundam 00 during the final battle. It was constructed with the combined data from all Gundam units seen in that series up to that point. Needless to say, it's very powerful. You see it mostly in the body of the small Gundam atop the "large head" portion.
Also from the Gundam 00, this unit features at least fourteen GN Drives, which leverage a "writer makes stuff up as he goes" power extracted directly from the baryonic isotope called GN particles. Those conic shapes are the Drives and the red mist represent the GN particles. Most machines from that series only featured two working in tandem, though at least one machine was constructed utilizing seven knock-offs at once, mostly for weapon systems.