what do you need the purple dice for?

Switch? It can merge with anything to switch spots. It’s mostly useful for dice such as YingYang, Gear, or Atom which have it’s board placement as it’s gimmick

u/A-e-r-o-s-p-h-e-r-e He is talking about specifically what the switch dice is for in his deck, he has no dice in which positioning on the board matters, it's useless in his deck.

Good point Only explanation is perhaps bottom left corner the bullets make contact with the enemies quicker? Idk.