Also they arent from alternate universes because the backrooms is multiversal. yeah they could be from other universes void spawn when the backroms built they dragged there but the void is also even biggrr than backrooms.
Honestly i have no idea why rattlers and smilers are fighting,, guess they are too territorial for prey. backrooms is harsh place and oid does not help. but why dont they just work together?
Smilers are a freak of nature as they are freindly unlike most void things so thats weird i understand why smilers and frowners fight