Some sentients are created with villainy in their servos - others are made villains by history.
Megatron rebuilds himself continuously. When the war first began on Cybertron, he constantly applied
new modifications to catch the Autobots unaware and under prepared. His spies are always on the lookout for new tech that will optimize his body into the perfect war machine. He is the bleeding edge of technology on Cybertron, and his enemies will pay the price for not keeping up.
We've already seen one interpretation of Cybertron-mode Megatron, but that was emphatically intended to be an earlier version of Generation 1 Megatron, while War For Cybertron is a new continuity, and this is thus a new character. Sure, it's influenced by G1, but what these days isn't? Someone needs to point out to Hasbro (or more likely, to the fans) that if you never do anything but throwback references, you also never make anything new for future throwback references.
WfC Megatron isn't just a fancy version of the G1 design. Like Animated Megatron, he's inherited a bit from movie Megatron, as well. It's not the "pile of shards and wires" design the movie favored, but it is very sharp and angular. He has a broad torso and a narrow waist, then massive flat feet to hold him upright. The knees are sharp points - remember, he started out as a gladiator, so those would have been killer if he kneed someone in the ribs.
The design of his body has lots of layers, which
is the strongest tie to the movie designs. It really gives the impression of a body that's had more and more tech added to it over the years: he wasn't just designed in this shape, like a car, it's the end result of his add-ons, like one of those horrible Japanese delivery trucks. Like Optimus Prime, he has his faction symbol on his back, though his isn't hidden. Megatron's is more recognizable, as well. It's stretched vertically, but that just makes it look even more threatening.
Megatron is slightly over 6" tall, counting the spikes on his left shoulder, and very nicely articulated. The head swivels, there are swivel/hinge joints for the shoulders, hinged elbows, swivel forearms, swivel/hinge hips, swivel thighs, hinged knees and swivel/hinge ankles. He doesn't have a waist, and although his hands have a very cool design, there are no wrists.
Megs is armed with his fusion cannon, though it's much larger and more complex than previous versions. The original thing was just a tube and a cube, while this thing looks like a real fake weapon. The cannon can plug onto either arm, but come on, you know it goes on the right. As Primus intended!
You may remember that we called Straxus' transformation "clumsy and inelegant." Well, we still stand by that, but it's possible that our impression of him was colored by comparison to Megatron,
here. Megatron is everything that Straxus isn't: the conversion is simple and smooth, the parts move past one another easily, and there's no idiotic third mode jammed in there needlessly.
Megatron's War for Cybertron altmode is a tank, because these days it's either that or a plane of some sort. The tank is just as angular as the robot was, and looks nothing like any real Earth tank. Well, okay, it looks something like an Earth tank, since it has treads and a cannon, but you know what we mean.
The proportions of the thing are similar to Megatron's tank from Transformers 2 - Voyager class release, not Leader Class.
It's short and round and looks like it's been smashed from above. There are some small prongs sticking out the front underneath the barrel: it's probably unintentional, but you can totally look at those as an homage to Armada Megatron. The tank's treads can fold underneath to create a hover mode, and honestly, you might end up leaving them that way most of the time: it's cool, and just that much more unearthly.
There are only four War For Cybertron
toys available so far, but Megatron is easily the best of the bunch. Bumblebee doesn't fit together as well as he should and he looks weird, Optimus Prime is small and the biggest selling feature of Soundwave is a completely unofficial fanmode. Megatron, meahile, looks cool as a tank, is killer as a robot, and converts between the two wonderfully. More like this, please.