MegaSeadramon is an Ultimate class Digimon that looks like a bigger, and redder version of Seadramon. The top of his head is made of gold, with a horn shaped like a lightning bolt, and green hair.
Digimon Adventure 01
MegaSeadramon first appeared as one of Myotismon's servants that guarded a bridge and blocks Ikkakumon. Ikkakumon fights against MegaSeadramon but the latter was too powerful. Then Joe's Tag of Relibility glowed and Ikkakumon Digivolves to Zudomon to defeat MegaSeadramon knocking him out into the sea.
Digimon Adventure 02
The same MegaSeadramon that worked for Myotismon survived from the fight with Zudomon, returns and is now under the control of the Dark Ring that the Digimon Emperor gave. Ikkakkumon once again fights the controlled MegaSeadramon. Armadillomon Armor-Digivolves to Submarimon to defeat MegaSeadramon, freeing him from the Dark Ring from the Digimon Emperor’s control. Happy, MegaSeadramon returns to the Digital World. He reappears again with several Dolphmon to fight BlackWarGreymon, but was easily wiped out by him.
A Seadramon that evolved systematically, he is body has become larger. He is mainly witnessed under severe environment around the Folder continent. The outer hull around his head has become harder, a blade has grown on his head, his defensive power has increased, and he is able to shoot electricity from the blade on his head. He has become more intelligent and is able to swim faster; he dives into the deep and murders his prey.
- Thunder Javelin
- Mail Strome (Maelstrom in Japanese version)
- Doramon Attack (Dramon Attack in Japanese version)
- Ice Blast (Ice Arrow in Japanese version)
- Tail Blade (Stinger Surprise in Japanese version)
- Ice Reflector (Ice Reflect in Japanese version)
- Thunder Blade
- Mega Ice Blast
- MegaSeadramon's mega form is MetalSeadramon.
- MegaSeadramon's champion form is Seadramon.
- In the English version he was voiced by Dave Guerrie, who also voiced Phantomon and Machinedramon.
- It is possible that this MegaSeadramon was the Seadramon fought in the lake by the Digidestined, later digivolved and then recruited in Myotismon's army.
- However, a similar theory which thinks MetalSeadramon was this megaevolved MegaSeadramon is completely impossibile, because the Dark Master was in his Mega form since ancient times where he also fought with original digidestined, and also because MetalSeadramon was conquering Digiworld when MegaSeadramon was in Real World with Myotismon.
- The scene in the bridge of Odaiba where MegaSeadramon is defeated by Zudomon with his hammer is partially inspired by the norse mythological battle of the titanic sea serpent Jormungand against the god Thor, where he also kills the serpent with his thunder hammer.
- MegaSeadramon is the only surviving of Myotismon's army, except Gatomon revealed being a digimon of DigiDestined (Kari) and Nanimon with his recruits who escaped before Myotismon was going in the Real World.
- He's also the only one that becomes good and still be alive, if excluding Gatomon that was already destined to be with Kari.