Bolas's Citadel [War of the Spark] Elf Advisor Set: Commander 2014 Type: Creature

Set: Commander 2014 Type: Creature — Elemental Beast Rarity: Rare Cost: {5}{G} When Grave Sifter enters the battlefield

They only specify the consequences should you fail

Set: Battlebond Type: Land Rarity: Rare Luxury Suite enters the battlefield tapped unless you have two or more opponents

Set: Commander 2011 Type: Artifact Rarity: Common Cost: {2} {1}

an enchantment

Bolas's Citadel [War of the Spark] Elf Advisor Set: Commander 2014 Type: CreatureSet: War of the Spark Type: Legendary Artifact Rarity: Rare Cost: {3}{B}{B}{B} 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. {T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.