Although I would have preferred to see the tech spec describe the persona of the Vehicon leader and evil mastermind of Beast Machines, they decided to give it a more RID spin as seen to the right. Oh, well!       > > > > > 

"Embodies the cruel and destructive nature of a nefarious leader.  Houses the spark of a Predacon, though newly proclaims himself to be a Decepticon -a display of his arrogence.  A battle-hardened commander who wants nothing more than universal domination.  Has led the devastation of countless worlds before coming to Earth, and is set on eradicating the Autobots.  Developed "emissary mode" to combine with his space cruiser and even the secret Autobot defense fortress in attempt to gain absolute power.  In robot form, he attacks with energy claws and sonic missiles."

Other Appearances: Well yes there have been quite a few other appearances!  The way I think of it, there was the persona that was G1 Megatron who took several forms in G1, G2.  Then the character that led rather foolishly in TF Armada, then Energon, then Cybertron.  Before becoming the Megatron who went back in time to fight in the Beast Wars and Beast Machines. IMHO, this is the culmination and final form of this Megatron character. 

1984: original "G1" Megatron
1990: Actionmaster Megatron
1993: G2 Megatron (electronic green tank)
1994: G2 Megatron (purple tank, air rocket)
1995: G2 Megatron ("gobots" car!)
1996: Original Beast Wars Megatron
1998: Transmetal Megatron
1999: Transmetal 2 Megatron
2000: Beast Machines Megatron (dragon)
2001: This version R.I.D. Megatron
2002: Megabolt Megatron (box says RID, but it's really Beast Machines season 2 version) & Armada Megatron
2004: Energon Megatron,  plus the smaller version of the same toy sold as a two pack with Powerlinx Optimus Prime
2005: TF:Cybertron Megatron