MTG Crucias, Titan of the Waves Deck by MTGA-Assistant-Meta

At the beginning of your end step, you may discard a card. If you do, create a Treasure token and choose ambitious or expedient. If you chose ambitious, seek a card with greater mana value than the discarded card. If you chose expedient, seek a card with lesser mana value than the discarded card.

Trample When Caldera Breaker enters, exile all Mountain cards from your library. When you do, Caldera Breaker deals that much damage to target creature or planeswalker an opponent controls. When Caldera Breaker dies, put all cards exiled with it onto the battlefield under their owner's control. Conjure four cards named Volcanic Geyser into your library, then shuffle.

As an additional cost to cast this spell, sacrifice a creature. Draw two cards.

Return up to one target creature card from your graveyard to your hand. Venture into the dungeon. (Enter the first room or advance to the next room.)

({T}: Add {B}.)

({T}: Add {R}.)