Post's Citadel - Bolas's Citadel (Post Malone) (SLD-1187) - Secret Lair Drop / Post's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
, Sacrifice ten nonland permanents: Each opponent loses 10 life.