First Appearance: Sentinels of the Multiverse: Shattered Timelines
Where it is: A disjointed region of metaphysical space that’s out of time with reality.
Primary Damage Type: Melee
Secondary Damage Type: Toxic and Infernal
Deck Concept: Most of Time Cataclysm’s effects are global, targeting heroes, villains and even environment cards alike. While most environment decks make sure they don’t target their own cards, Time Cataclysm throws that caution to the wind.
Biggest Global Effect: Marsquake!: At the end of environment turn, deal each target 2 melee damage. At the start of the environment turn, destroy 1 villain ongoing card, 1 hero ongoing card, and 1 environment card.
Worst Card (for the Heroes): Crushing Hallway: At the end of the environment turn, 1 player may discard their hand to destroy this card. At the start of the environment turn, deal each target 4 melee damage and destroy all hero ongoing cards.

Odd Ways to Win (Achievement Time):
Charging Triceratops (8HP): Reduce damage dealt to this card by 1. At the start of the environment turn, this card deals the target other than itself with the second lowest HP 3 melee damage.
Surprise Shopping Trip: Whenever a card enters play, deal each target 1 melee damage. At the start of the environment turn, destroy this card.
Crushing Hallway: At the end of the environment turn, 1 player may discard their hand to destroy this card. At the start of the environment turn, deal each target 4 melee damage and destroy all hero ongoing cards.
Marsquake!: At the end of environment turn, deal each target 2 melee damage. At the start of the environment turn, destroy 1 villain ongoing card, 1 hero ongoing card, and 1 environment card.

How to Escape:
Time Cataclysm is perhaps the most evenhanded environment deck to date. I’d deal with Crushing Hallway as soon as possible. Destroying all hero ongoing cards hurts a ton. You’ll also want to get rid of Marsquake! too but the only way to do so is with a hero that targets environment and/or ongoing cards. The Visionary and countless others can help get rid of environment cards, but Time Cataclysm does have a reset card of sorts.

Rift in Time allows you to destroy 1 environment card at the beginning of the environment turn, so that circumvents the need to play as a hero that can destroy environment cards, but you have to be really lucky to top deck Rift in Time. You could always keep one copy of Rift in Time in play just in case you encounter a less desirable environment card in the future. The worst thing Rift in Time does is play an additional environment card per environment turn.

Outside of that strategy, I’d be weary of Surprise Shopping Trip as it deals each target 1 melee damage each time a card enters play, but it only last for one round—you could just not play a card that round—and Passing Tumbleweed provides yet another means to destroy environment cards. Unfortunately, it only has 1 HP and there’s only one copy of Passing Tumbleweed in the deck, so it’ll be more difficult to keep it in play than it is to draw into and keep Rift in Time in play, but Passing Tumbleweed is a cheaper means to get rid of environment cards should you devise a way to redirect damage. I’m thinking Legacy or The Scholar are your best bet for damage redirection.