We need a Red and a Blue:
Red:
Search your deck for a Pokémon and put it into your hand. (Shuffle your deck afterward.)
Blue:
Until the end of your opponent's next turn, your Pokémon's attacks do 10 more damage to the Defending Pokémon for each prize card you have taken.
We also need a Battle Tree stadium:
Battle Tree:
Each Pokémon's attacks (both yours and your opponent's) do 30 more damage to the Defending Pokémon.
And maybe an Ultra Space stadium?
Ultra Space:
Once during your turn, before you attack, search your deck for an Ultra Beast and put it into your hand.
Do you know what would be cool? A Double Battle stadium.
Double Battle:
Each player may have 2 Active Pokémon. If this stadium is discarded, return one of your Active Pokémon to your hand.
Maybe not the last one. But still.