List of a few transforming power-ups that I have come up over time. Unlike Trinkets that are mainly excuse for lewd scenarios, these are to give cool transformations for a character. Idea is that how much of a percentage of a Powerup is used the more noticeable transformation is. 25% - costume change, 50% - partial transformation, 100% - full transformation. Here are the ones I have used so far:

Ekitai Lamp - Water based transformation/powers. Example here
Kaen Crown - Fire based transformation/powers. Example here
Ginga Pin - Galaxy based transformation/powers. Example here
ToriFlu - Bird based transformation/powers. Example here

If you like my art please consider supporting my Patreon