Somehow I doubt Aganos would fit…
Ra better summon up an extra large coffin then, that or skip the whole coffin bit and just throw them into the huge tornado and have the rest happen.
Cinder - according to his story, he wears a suit to contain his
nuclear energy. He could for instance take off his helmet and explode
with supernova of energy.
Jago - a phantom of Tiger (similar to what we see when activating his
Instinct) would appear, and attack opponent with claws and bites, Jago
meditating like a boss.
Aganos - he could bury opponent in rubble, and then brutally pull him out.
Sabrewulf - similar to Jago`s phantom Tiger but more violently.
Kim Wu - her dragons could wrap around opponent and bite him, similar how Shao Kahn in MK9 story mode died.
TJ Combo - a series of not sportsman blows (step on opponent toes, blow below waist, headbutt, ear bite ( ͡° ͜ʖ ͡°) etc.)
Glacius - freezing opponent to block of ice and smash it OR calling another glacius for some Noob Saibot action.
Tusk - honestly IDK, running opponent over with his snowmobile? lol
Kan Ra - some kind of choking opponent with bandages, or mummifying opponent.
Thats some ideas that came to my mind just now, I hope you`ll share some of yours too.