If I use Steenee's "Captivate" attack while Spikemuth stadium is in play, does the opponent put any damage counters on their Pokemon?
No, Captivate would not trigger Spikemuth since it was not moved during the opponent's turn.
CaptivateSpikemuth




x2
CaptivateSwitch 1 of your opponent’s Benched Pokémon with their Active Pokémon.
Water GunIf I use Steenee's "Captivate" attack while Spikemuth stadium is in play, does the opponent put any damage counters on their Pokemon?
No, Captivate would not trigger Spikemuth since it was not moved during the opponent's turn.