Creature concept sheets or a personal world-building project. The goal is to turn videogame characters into kaijuu (giant movie monsters like Godzilla). I also write a bit of backstory fluff to integrate them, along with other characters I keep human, into a cohesive world.
In the kaijû-fication process, I try to keep as many elements as possible from the original design and convert them into something believable for a kaijû: a crown becomes spikes, a hammer becomes a club tail or dream magic becomes hallucinogenic gaz.