Day's Undoing [Commander Masters] Nightmare Horror you secretly choose a card

you secretly choose a card from your hand and a standing tactic from your collection to either guard your ships or blast your opponent's ships

Set: Odyssey Type: Basic Land — Mountain Rarity: Common ({T}: Add {R}

For each counter removed this way

Set: Portal Three Kingdoms Type: Basic Land — Island Rarity: Common ({T}: Add {U}

Day's Undoing [Commander Masters] Nightmare Horror you secretly choose a cardSet: Commander Masters Type: Sorcery Rarity: Rare Cost: {2}{U} Each player shuffles their hand and graveyard into their library, then draws seven cards. If it's your turn, end the turn. (Exile all spells and abilities from the stack, including this card. Discard down to your maximum hand size. Damage tears off, and "this turn" and "until end of turn" effects end.)