Mirage Stadium (Skyridge 132/144)

Whenever a player tries to retreat a Pokémon during his or her turn, that player flips a coin. If heads, that player retreats that Pokémon (and discards Energy normally). If tails, that Pokémon can't retreat this turn (the player doesn't discard any Energy).

Card rule

This card stays in play when you play it. Discard this card if another Stadium card comes into play.