Recently I started talking more about, as well as doing a little bit of prototyping for, that character action semi-RPG game I've mentioned before, called HYPERNULL.
The thing about HYPERNULL's concept, being a setting primarily inspired by MUGEN cheapies, is that I have very strong concepts for the game's "superbosses" right off the bat (borrowing the term from the Kingdom Hearts series for optional sidequest boss fights, usually more difficult than main quest combat) simply by basing them off of notable real-world cheapies as cameos.
Two such characters that stand out as superboss concepts for HYPERNULL are oaev (aka οαεν) and Already Broken (specifically 0.49).
oaev would be a "puzzle boss" of sorts. Any time in which you perform a Level 1 Super Attack, or at certain points in the fight regardless, she will immediately disable the stance it belongs to (recall that K-Terminal has three "stances": Claws, Brawling, and Gunblade), replacing it with the " D e l e t e d . " stance, rendering you unable to attack until you switch out of the stance. This also disables any ability in your deck linked to that stance. Essentially, this would encourage you to bring a deck that's balanced between two or three stances rather than relying on a single stance. Additionally, I would want to do the character's presentation as much justice as I can; with an unsettling introduction cinematic hanging on her featureless face for an uncomfortable amount of time before flashing to a "normal" face as she berates K-Terminal before the fight. Plus, a Non-Standard Game Over when being defeated by her with a recreation of her victory screen... possibly taking a creative liberty here to actually fill the victory quote box with a taunt that hints at how to beat her gimmick ("Maybe you shouldn't be so careless as to devote everything to a single combat style, pitiful Null.").
Already Broken might be a more straightforward high-speed humanoid boss fight with intricate attack patterns... once the fight actually starts, that is. Rather, the moment you enter her arena, before you're even given the option to check what command deck you have equipped, she instantly launches into a lengthy and complex desperation style attack, sort of like... well, I know it's quite on the nose and cliche to bring this up in 2024, but basically like the Sans fight in Undertale. Only after you've survived this initial onslaught would she finally appear, blaring a distinct eurobeat battle theme and taunting you during the boss introduction screen. There would be a Non-Standard Game Over, but only during the opening desperation move.
Also, if you're thinking about characters like Infinite Soulabyss or Undefined Universe, well... There's always the idea of making a Bloody Palace / Olympus Coliseum style optional battle arena starring the two as a couple, pitting you against waves of common enemies and occasional boss refights.
