Liliana's Mastery [Game Night 2018] Unknown Planet Set: Ikoria: Lair of Behemoths

Set: Ikoria: Lair of Behemoths Type: Artifact Creature — Giant Rarity: Rare Cost: {3} At the beginning of combat on your turn

and the sea answers

Then you may cast an instant or sorcery spell with mana value less than or equal to the other result from your hand without paying its mana cost

then why are you dead

Liliana's Mastery [Game Night 2018] Unknown Planet Set: Ikoria: Lair of BehemothsSet: Game Night 2018 Type: Enchantment Rarity: Rare Cost: {3}{B}{B} Zombies you control get +1 +1. When Liliana's Mastery enters the battlefield, create two 2 2 black Zombie creature tokens. "There are so many of them. It seems they've just been waiting for someone to serve."