Thread:TheDigger1/@comment-27109830-20160609200212/@comment-26220697-20160609213044

Frisk vs. Madotsuki (Yume Nikki): Shy child protagonists of surprisingly dark indie RPG's, who always have their eyes closed, travel through strange and mysterious worlds, and are often depicted as wielding knives as their main weapons.

Chara vs. Giygas (Mother): RPG antagonists who were raised and cared for by a loving couple of a different species, who ended up trying to kill every member of the species that said couple was from, with Chara trying to kill all the monsters, and Giygas attempting to invade Earth and kill the humans. After the destruction of their bodies, they became embodiments of destruction and evil with immense power.

Toriel vs. Rosalina (Super Mario): Kind and caring females who act as motherly figures to creatures of different species, with Toriel housing the humans that come into the Underground before they leave and Rosalina acting as caretaker for the Lumas. Despite their kind and loving exteriors, they have much more power and a much sadder backstory than expected.

Sans vs. The Judge (OFF): White, constantly grinning monsters from indie RPG's who judge the player themselves for their actions in the game. Both are protective over their more naive younger brothers, are some of the only characters in the game who know of the outside force controlling the main character, and act as the final bosses of the routes when the player decides to just murder everything.

Papyrus vs. Sir Daniel (MediEvil): Goofy skeletal knights who wish to become great heroes and warriors.

Undyne vs. Pearl (Steven Universe): Female inhuman knights known for wielding spears, which they can a near-unlimited amount of if needed, who greatly respect the kindly and powerful warriors who trained and led them, Asgore and Rose Quartz respectively.

Mettaton vs. Hatsune Miku (Vocaloid): Artificially-created superstars who prefer to put on shows for their audiences over fighting, but aren't slouches when it comes to combat.

Asgore vs. Subject Delta (BioShock 2): Physically imposing, but kind and caring, fighters known for wielding massive weapons in conjunction with magic. Both were trapped in places under the surface, Rapture and the Underground respectively, which they hated and wanted to leave. Despite their imposing exterior, they never killed anyone if given the choice. Both of them lost all of their family, including an adopted child, but ended up offering their souls to children to help them live a good life. In the end, they were both killed by a psychopath in an attempt to promote their way of life.

Flowey vs. Dimentio (Super Paper Mario): RPG antagonists who pretend to be polite and light-hearted at first, but eventually reveal themselves to be some of the most psychotic, cruel, and cunning characters in their games. Near the end of their games, they absorb powerful artifacts, the Chaos Heart and the six human SOULS respectively, transforming into god-like creatures with the power to control and wipe out all of existence if they wanted to. Both of them appear undefeatable at first, but the combined power of some holy artifacts make them vulnerable and let the hero stop them.

Asriel Dreemurr vs. ZeedMillenniummon (Digimon): Reality warping beings of great destructive power, who are capable of wiping out and resetting universes on a whim. Despite their power, both of them started out less powerful beings who ended up dying, only to be brought back through unnatural means, Asriel by being brought back by Alphys as Flowey and ZeedMillenniummon being created by a Millenniummon's corpse being possessed by a dark spirit.

Proto Man vs. E-123 Omega (Sonic the Hedgehog): Red robots with large arsenals who turned against their creators and chose to follow their own paths.

Mega Man X vs. Metal Sonic (Sonic the Hedgehog): Blue robots created as better versions of well-known blue heroes, who have the power to copy the abilities of the people they fight.

Zero vs. Meta Knight (Kirby): Badass swordsmen with incredible power, who act as mentors and friends to the less experienced main characters.

Sigma vs. Ridley (Metroid): Video game villains who, no matter what punishment they take or how much damage they sustain, never seem to die. Either through being physically rebuilt, or just dumb luck, they always come back to attack the main heroes.

Dr. Weil vs. Porky Minch (Mother): Intelligent, depraved humans whose aging has permanently stopped. They've been around for centuries, but their bodies have degraded pretty badly at this point, forcing them to rely on machinery and cybernetics to do everything for them. They've even come to rule over large influential cities and at some point plan to destroy the world like the genocidal maniacs they are. They don't exactly die at the end of their games either, though the state they end up in is arguably much worse.

Bass vs. Veil (Pulseman): Black-colored robotic rivals to the mechanical main characters.

MegaMan.EXE vs. Haseo (.hack): You told me about this one, so I'm pretty sure you know what the connections are.

Bass.EXE vs. Beelzemon (Digimon Tamers): Dark digital badasses who, unlike other members of their kind who partner up with humans for power, decide to prove that humans are worthless and that they can be strong without them. Using their ability to absorb the data of their fallen enemies to boost their strength and get new powers, they wander the wastelands of their digital worlds, eventually becoming some of the strongest enemies the main characters have faced. While Beelzemon eventually realized the error of his ways and grew to respect humans, Bass did not.

Geo Stelar vs. Ben Tennyson (Ben 10): Once-ordinary kids who have family working in space-related jobs, with Geo's dad being an astronaut and Ben's grandpa being a former alien hunter, who came in contact with an alien object that bonded with them, Omega-Xis and the Omnitrix respectively. They then used the powers granted by the object to become a superhero. Also, they both have several different forms they can take on, Geo with his Noise Change forms, and Ben with the aliens he can transform into with the Omnitrix.

There's probably some Mega Man matchups I'm forgetting, but these are what I could remember at the moment.