Arena (Battles 2)
Bloons TD Battles 2 features nine arenas. Arenas function as the "ranks" in the game, with players being match-made with other players in the same or close arenas as their own. Each Arena has its own set of available maps, and later arenas give increased Monkey Money and Tower XP. Additionally, Arenas each have their own medals which are unlocked at the end of a season based on the highest arena a player reached that season. These medals feature the Arena's corresponding Bloon type as well as the season in which the medal was obtained.
Red Bloon Camp
The first Arena in the game. In this arena, Bloon Mods are disabled and the League serves no purpose other than cosmetic
Yellow Stadium
The Yellow Stadium is unlocked upon reaching 30 trophies in Red Bloon Camp. The Arena introduces Bloon Mods and properly implement the weekly League system as a method of promotion, though you cannot be demoted to Red Bloon Camp.