Any fics where different supernatural forces mix weird?

A prime example now that I think about it would be something like what happened to Scarlet Witch in one of the DC/Marvel crossovers, where when she crossed into DC she accidentally accessed the same chaos that the Lords of Chaos do.

It doesn’t have to be that overpowered though. Maybe an MCU sorcerer goes to DC, losing access to spells that required different entities ie the Bands of Cytorrak, but eventually learning to tap local entities and forces ie the Parliament of Trees.

Basically, I’m looking for magic working different due to being in a different cosmology or interacting with something from a different setting.