So I was playing today and came across the following danger room: this. I took the screenshot from the top so the Puppies wouldn't see me. It consisted of two large square spike traps (like the Figure Eight and Slime Spawner rooms) inside which were 4 respawning Gun Puppies and around which were four lines of regenerating Ghost Blocks. Stage 1 was only Scuttlebots, stage 2 was Scuttlebots and Retrodes, and stage 3 was Scuttlebots, Retrodes, and Mecha Knights.
If any common wiki editor comes across this room again, they could add it to the list and give it an appropriate name. I know the list isn't meant to be exhaustive, but I've been playing for some time and haven't found any other that aren't on the list.
I happened to stumble across it in another Power Complex (Beast this time; last time it may have been Construct) and got a better screenshot of it: this.
I propose that it be called Caged Puppies, unless anyone has a better idea. I'll create Acid-Snow-Wiki or something to add it to the list in wiki if no one else does.