This popped into my head while i was in the arena.Two minions were killing each other,so why not we have a monster arena?You Basically are in a "fight" getting pips until you summon a special monster card.It then takes you and onlookers to bleachers once both teams have a monster.(note there can be 2 monsters and 2 people,as the monster goes into a circle-thing.)
The monsters then attack with spells and the winning team either
A:wins a copy of the enemy monster B:100-200 gold,depends how many monsters C:Treasure cards D:clothing(pets and jewelry too) E:A kind of clothing that lasts for a certain amount of time(i.e 24 hours,48 hours,72 hours or 96 hours.It is marked in your backpack by a pocket watch