Just gonna make it short.
- Purpose is to test out your weapons' strength/range and armors/units.
- Sandbox only. (If you want it in normal mode then it'll have to be boring objects to prevent unsealers taking advantage.)
- Range rooms (Laser fence and such.)
- Trap rooms (Test out your Dress Plate, how quick can you escape from frozen trap. Etc.)
- Melee room (If possible to have an enemy with unlimited health to capture the amount of frames of the melee animations.)
- If it's set in Seabeds, drop glitch with a teleport nearby for repeat testing.