|“||I am not one to leave my comrades behind. In fact, I am always behind their backs.||„|
MetalSeadramon (メタルシードラモン ?, Metarushīdoramon) is an Ultimate-level Aquan-species Cyborg Digimon who operates as the leader of the Boundary Crossers, a group of Digimon that travel between universes to retrieve any rogue Digimon that may have escaped the Digital World.
MetalSeadramon joined the Boundary Crossers as their third recruit, making him the fifth official member. He was a longtime acquaintance of Darkdramon's. The two met again after a few years while Darkdramon was looking for recruits in the surroundings of Access Glacier; upon their encounter, Darkdramon immediately explained the situation and his objective, which piqued MetalSeadramon's interest. Being capable of evolving into the more mechanical GigaSeadramon proved to be a highly useful asset, as GigaSeadramon was later equipped with the necessary tools to allow the Boundary Crossers to initiate their mission. The Boundary Crossers were technically all set to go after GigaSeadramon's modification, but BanchouLeomon suggested they recruit more members before taking off.
MetalSeadramon has a caring, easygoing disposition. He is somebody who always cares about the well-being of all the Boundary Crossers, and is the only one aside from Darkdramon to get along with everyone on the team. MetalSeadramon is quite wise for his age; because of his wisdom and easygoing character, the others view him as a 'voice of reason' and often talk with him about their troubles. Being somebody who will always help out a friend in need, MetalSeadramon is an almost fatherly figure to some members of the Boundary Crossers (particularly ZeedGarurumon), but enjoys a good battle now and then and is always up for a match when the situation calls for it. He is great friends with the elderly RustTyrannomon.
- Ice Arrow Flurry: MetalSeadramon attacks the opposition by spitting large, sharp icicles from his nostril cannon.
- Electro Blaster: MetalSeadramon looses a powerful electric orb from the cannon on his snout that explodes on contact.
- Laser Blade: MetalSeadramon extends energy blades from his fins and horn to slash an opponent with multiple times.
- Nanomech Heal: MetalSeadramon sends nanomachines through himself and his friends, restoring their HP.
- Ultimate Stream: MetalSeadramon looses a massive energy stream from his snout to inflict great damage.
MetalSeadramon is capable of evolving into an even more devastating form, that being GigaSeadramon.
In this evolved form, GigaSeadramon's overall attributes are greatly amplified compared to the already powerful MetalSeadramon, but the most important point of interest is that he is armed with spacetime oscillation waves used to open Digital Gates. These waves serve to create a stable tunnel through spacetime in tandem with Mastemon's spacetime-travelling abilities, allowing the Boundary Crossers to safely travel through the vast continuum in order to fulfill their mission. Due to his enormous size, GigaSeadramon transports his teammates inside a chamber in his head.
- Gigaton Hydro: GigaSeadramon blasts a stream of water onto his opponents that exerts great pressure.
- Giga Missile: GigaSeadramon launches several barrages of missiles from all over his body to ravage the opposition.
- Shining Ray: GigaSeadramon blasts two energy rays from his mouth at the opposition.
- Nanomech Heal Plus: An upgraded version of Nanomech Heal that restores status ailments on top of greater HP recovery.
- Giga Sea Destroyer: GigaSeadramon looses a gargantuan missile from the cannon in his mouth to blow the opposition to nothing.