5 years ago when I played SC2 for the first time there was plenty of (iirc) “Arcade” maps which were UMS, and I’m pretty sure, community made. Are you perhaps talking about early days of SC2 when that still wasn’t a thing or? One map I was most impressed by and had lots of fun playing it, was called “Assassins”. I won’t explain what it is, but if someone took it to develop a game based on it, I strongly believe(d) that it’d be another hit game that spawned from SC