Which need to be separate from Mai's and Yuki's 32×32 balls because…
they have a delay cloud, whose radius absolutely has to be stored
redundantly, rather then deriving it from the [age]? Same for the decay
frame count. And the _update() function was copy-pasted from the knife
one…
Part of P0079, funded by -Tom-.
Since they're determined by the order of sprites in a .BFT file,
they're best auto-generated by an enum as much as possible.
Part of P0074, funded by Myles.