Arena Training Mode
The general idea:
Giving players a permanent place to fight real enemies at zero energy cost but has no rewards other than tiny amounts of Heat and bragging rights.
Pros
Costs Zero Energy to play.
Gives out *tiny* amounts of Heat.
CONS
No item drops
No crown drops
Misc.
Could create a High-Score / Fast-Time Leaderboard: Fight for bragging rights!~
Could have two modes 4-player normal arena-style
8-player tag-team (each player has 1 Life, or permanent rotation swapping with no life limit).
I was intigued by the Training Hall holding more than 4 players.
Cool idea. This would be WAAAAAY better than the tiny enemy cage in the advanced training hall. But you shouldn't get heat from training, just saying.