My suggestion is to implement another mode where users can play against their friends, clan members, or bots with decks that usually aren’t possible in the normal game. For example, they could have decks with 8 little princes, all of the super cards, all evolutions, etc. Also, since they are playing against their friends and clan members, this won’t hurt any of the actual modes and other players. It would also be very fun as a player to also be able to customise the different values for each card in this game mode to create new cards. For example, being able to double the health of archers or make the sparky do 1 damage. This would be a fun way to playtest interactions which aren’t possible in the real game.