From Bulbapedia, the community-driven Pokémon encyclopedia.
Neon Colosseum (Japanese: カジノシアターコロシアム Casino Theatre Colosseum) is the fourth Colosseum in Pokémon Battle Revolution. The battle theme is Fortune Battles. The Colosseum leader is Colosseum Leader Rosie. Like most other Colosseums, there are 7 battles in all.
Neon Colosseum is located on a blacony high atop a building in the middle of Pokétopia. It appears to be enclosed in plexiglass. Battles here are depicted as taking place in the middle of the night. However, the Colosseum is lit by rotating spotlights all around. In addition, lights surround the Colosseum, attacked both to the outside balcony and the inside walls. As its name suggests, Neon Colosseum has many neon lights. Behind the arena is a giant roulette wheel, known as the Pokémon Wheel (See below).
The battle theme, Fortune Battle, is unique and, if you are not good at it, frustrating. Before the battle starts, both Trainer's Poké Balls are put on a roulette wheel caled the Pokémon Wheel. Each Trainer is given four Poké Balls. When tha player starts the Fortune Wheel up, it will spin around until he drops a ball onto it. The player must use the Pokémon the ball lands on as his first in battle, no matter whether it is his or his opponents. The other Trainer also drops a Poké Ball, and then the player, until all four Poké Balls, or three if it is a Single Battle, have been dropped. Therefore, it is a good idea to use Rental Pass Pokémon, as opposed to strong Custom Pass Pokémon, in case your opponent gets your own Pokémon. This is the only Colosseum where the Level 30 open rule will round up your Pokémon's levels to match your highest leveled Pokémon.
After you beat the game, you may select the level 50 All rule. The rules do not change.
Beating Neon Colosseum for the first time in Level 30 Open mode gets you Pikachu Gloves, a custom battle pass with Neon Colosseum in the background, 46 items in the shop, and 325 Poké Coupons. Beating Neon Colosseum for the first time in Level 50 All mode unlocks 24 pieces of gear in the shop. Also, when the player beats Rosie for the first time in Level 50 All mode, they obtain her Roserade outfit. There is a small chance of Rosie wearing a shiny outfit when you battle her in Level 50 All mode. If the player beats her while she is wearing a shiny Roserade outfit, they will obtain a shiny Roserade outfit of their own.
The default mode of battle here is Double Battle. An option to change this to Single Battle is unlocked after beating Rank 1 for the first time.
The Pokémon and Trainers are not set, except during the first time you battle there, at Rank 1 Level 30 Open, and the first time you battle using the Level 50 All mode, Rank 1 Level 50 All. The Trainers, and the Pokémon they have, go as the following during Level 30 Open, Rank 1: