I don't know why a read a lot about Clash Royal of this forum, but i'm a PC (running Linux OS) player, and i don't really know about Clash. I played it maybe 2-3 hours last year on my phone because i was curious for the buzz, but i generally don't play out of my computer.
I did play hundreds, thousands, of games since the first NES, then Megadrive/Genesis, and the PC all the way until today. So i may be influenced by many many games, movies, books, dreams, comics, talkings, IRL experience and all.
Friendly fire = the hits affect enemies, player and allies
It would have infinite range, BUT because cannot shot at Close and Medium range, and because of terrible speed, and because of weakness, it would be quite easy to destroy.
When transforming, it could die from one single shotgun hit, i guess.
Impact zone, i was thinking as large as Close Range circle, because i don't imagine a big bomb falling, but more like a rain of shrapnel or alike.
For it to work more or less, we would need walls and other obstacles, and manual deployement phase, at least inside a given zone.