Beast Wars Megatron (AKA Megatron II, although this isn't highly accurate) took the name from the Transformers holy document, the Covenant of Primus, which spoke of a great destroyer by that name (it's a common misconception that he took the name from the Decepticon leader, Megatron, from the G1 series). He was chief antagonist during the Beast Wars and Beast Machines saga and led a team of Predacons (latter day successors of the Decepticons) in Beast Wars, later Vehicons in Beast Machines.

Similar to the original G1 Megatron, this Megatron had his firearm (usually) attached to his arm in his robotic mode - his tail in the transmetal dinosaur mode, and his beast-mode head in his original beast form and the later dragon form.

He had nine known modes:

1. Inital Mode, Appearance Unknown aside from face
2. Pre-Transmetal mode, Alternate Mode is a organic-appearing T-Rex with a purple hide.
3. Transmetal, Alternate Modes are a metallic T-Rex with a pair of fanjets which allow flight.
4. Transmetal II, actually the result of the combination of his spark with the original G1 Megatron's spark, alternate form was that of a fire-breathing dragon.
5. A modified version of his Transmetal II form when he attempted to purge his organic element from his system.
6. DoubleChanger {Noble/Savage in US} formed entirely from his organic section when the purge finally took place but his personality ended in the wrong half.
7. The "Megabolt" form, a giant orbiting station/spaceship that transformed into a likeness of his head.
8. A drone which his spark temporarily resided in after he was driven from the Megabolt.

1. "Optimal Megatron", a name coined by fans; from the Beast Machines finale, in where Megatron takes Optimal Optimus' powerful discarded body, and removes the beast mode.

He died fighting Optimus Primal in the Beast Machines finale, falling into the heart of Cybertron and bringing about a new age of technorganic existence.

This was the only incarnation of Megatron that never took the name of Galvatron.

Megatron was voiced by David Kaye(US) & Shigeru Chiba(Japan).