You may play only 1 Stadium card during your turn. Put it next to the Active Spot, and discard it if another Stadium comes into play. A Stadium with the same name can't be played.

Each player who has any Tera Pokémon in play can have up to 8 Pokémon on their Bench. If a player no longer has any Tera Pokémon in play, that player discards Pokémon from their Bench until they have 5. When this card leaves play, both players discard Pokémon from their Bench until they have 5, and the player who played this card discards first.