[Endoperez]

On the other hand, consider the arena mechanic. All players may spend resources, and only one will benefit from it. If the price is worth a big risk, winning and not losing your thug will be very nice indeed.

If the arena event is too good, it will become unbalanced, and the mods that improve the arena might be banned from MP (compare to mercs).

Banning AI from sending in pretenders or uniques would be good, with no downsides that I can see.