I still have to get it hammered out what's up with Joker since he's Sora's guardian angel, which may or may not have meant him pissing off Joker by proxy, which may or may not have meant that Joker used Angel invisibility to sneak in and fuck up one of his spells at some point.

Maybe Sora doesn't even need to be involved. Maybe Joker just heard about Strange and decided to fuck with a rich douchebag. ~THE SKY'S THE LIMIT~