Series: Beast Machines
Magmatron's robot mode is a very organic-looking combination of his three dinosaur components. The T-Rex forms the lower body, chestplate, and right shoulder, the Seasaur provides the arms and arm shield, the pteranodon becomes the head and, well, ears. Really huge ears. Anyway, Magmatron makes for an imposing figure and is quite posable, though with a few restrictions. The three components hold together very well, the only thing that sometimes gets loose is the seasaur's head on his left shoulder. Magmatron carries a missile launcher (part of the T-Rex), but the weapon doesn't quite fit into his hand correctly. All in all, though, a good robot mode with only minor problems.
Magmatron splits into three different beasts. One is a dark blue T-Rex, the second a red pteranodon, the third a greenish-gray aquatic dinosaur (called seasaur, not sure what the proper name is for this one). The T-Rex offers the most play value in this mode, being quite posable and offering some features such as missiles launching from his mouth. The pteranadon can flip his wings somewhat, but is unremarkable apart from that. The seasaur is an acquired taste, I think they made his neck a bit too long. All three animals manage to look good, though.
The three dinosaurs can combine into a very strange-looking "fuzor", a gestalt beast. The T-Rex forms the head and forelegs, the seasaur forms the butt and hindlegs, and the pteranadon just snaps onto the top. This is by far the worst of Magmatron's three modes and can comfortably be left aside.
Magmatron originally was a Japanese exclusive figure, the main bad guy of the Japanese Beast Wars Neo line. Target toystores brought him to the US as part of the Beast Machines subline called "Dinobots". Since all other Dinobots were Maximals, Magmatron was also classified as such. His tech spec still hints at his Destron origins by calling him "emperor of destruction" (the traditional Japanese title for the main bad guy, sort of like the Autobot Prime/Convoy title). Finally, Magmatron has been brought back from oblivion to star as the main bad guy in IDW's upcoming Beast Wars comic series.
As a toy Magmatron is a mixed blessing. The robot mode is very cool-looking and offers very little to complain about. The beast mode with the three separate animals is okay, though no more than that, and the fuzor mode is just ridiculous. If you decide to leave Magmatron in robot mode (and you should, the transforming procedure is quite complicated), then you have a very good toy to display or play with.