There are 10 Colosseums!

Gateway Colosseum

In this Colosseum, you may only enter with Pokémon from the Rental set. However, when you defeat a person, you are capable of exchanging Pokémon with the trainer you defeated just like in the Battle Factory

Colosseum Leader Joe

Main Street Colosseum

In this Colosseum, you are in a Knockout Battle. You need to defeat each of your opponents or you will lose completely

Colosseum Leader Taylor

Waterfall Colosseum

In this Colosseum, your Team Order is decided by your Opponent, this required the most strategy as you do not know who's coming out next

Colosseum Leader Marina

Neon Colosseum

In this Colosseum, your Team Order is decided Randomly via a Roulette. It is unlocked by defeating the Waterfall Colosseum.

Colosseum Leader Rosie

Crystal Colosseum

In this Colosseum, the battles are done in a 16 Person Tournement style. It is unlocked by defeating the Waterfall Colosseum

Colosseum Leader Voldon

Sunny Park Colosseum

In this Colosseum, you are in a Knockout Battle. You need to defeat each of your opponents or you will lose completely. It is unlocked by defeating the Neon Colosseum.
Round Two turns this Colosseum into a Baby Pokémon battling area

Colosseum Leader Sashay

Magma Colosseum

In this Colosseum, it is a 6 Trainer Tournement including the leader. You need to get through them all to win. It is unlocked by defeating the Sunny Park Colosseum.

Colosseum Leader Terrell

Sunset Colosseum

In this Colosseum, 12 Pokémon are Randomly selected and you and your opponents are each given 2 Pokémon. You must go through with these Random Pokémon to win.

Colosseum Leader Dusty

Courtyard Colosseum

In this Colosseum, you are in a Knockout Battle. You need to defeat each of your opponents or you will lose completely. It is unlocked by defeating the Sunset Colosseum.
Round two has you battling through 100 trainers

Colosseum Leader Kruger

Stargazer Colosseum

In this Colosseum, your Team Order is decided by your Opponent, this required the most strategy as you do not know who's coming out next.
Round two has you battling 8 sets of 4 trainers, all with strong powerful Pokémon

Colosseum Leader Mysterial