"There's a lot of magic systems interacting with each other here but wishcoins are pretty simple, if sometimes awkward to explain." She pokes her head into Arda. The evil disappears. "Eos - the same world ingot powers like Keziah and Céleste's are native to - also has 'mints', who can make coins. Coins are made out of pain, so we spend a lot of time exploiting masochists. It's a triangle to do something little like flick a switch or braid your hair or iron a shirt, a square to conjure most smallish nonmagical objects, a pentagon to learn a language or apply most traits that can reasonably apply within nonmagical species variation for the target, a hex for a single issuing of a magical superpower, star if you want to terraform a whole planet, it takes an evil to apply magical traits that will persist through torching, a niner will impose stable magical conditions across an entire subworld, a tenner's enough to create a new subworld in a sheaf or affect many subworlds or do something that just requires a ridiculous amount of oomph. Haven't had anyone try for the level past that so far; they go up exponentially. The most common sapient species can't actually make anything bigger than a star without being magically augmented."