Catastrophe
In the Card System, a type of play that causes a major effect on the game.
Only one Catastrophe card may be played during any game. Once it is played, the Catastrophe card remains in the center of the Battlefield for the rest of the battle as a reminder that it was played. (It does not replace any Place cards already or subsequently on the Battlefield unless the Catastrophe card explicitly prohibits Place cards.) Any Catastrophe cards that are subsequently revealed go immediately into Exile and have no effect on play.
A Catastrophe card must be the very first card that a player plays during their turn (during the Draw phase). Otherwise the card has no effect.
Icon credit: Lorc on Game-Icons.net