The scientists that created the gundams were captured by OZ. OZ forced them to make new gundams. Reluctantly and without choice the scientists did so. There were two gundams. Vayeate was one of them.
The Vayeate has some pretty decent features. It's got a camera eye, which lets it see better than any of the other gundams. Pretty useful. Yet not as cool as the generator, a big generator on the Vayeate's back that powers the beam cannon. Every once in a while, a lid opens on the generator and releases all of the stored heat produced.
The beam cannon is just like that of the Wing gundam's (except probably more powerful): it only has three shots. It is powerful, though, and the Vayeate's main weapon.
The Vayeate is destroyed when Quatre goes crazy in the wing ZERO and gets in a fight with Heero. Trowa gets in the way of a blast to protect Heero, and the Gundam's arm gets blasted off. Around 10 minutes later, the gundam blows up.