Bolas's Citadel [War of the Spark]

Bolas's Citadel [War of the Spark]Set: 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.

Set: Shadows over Innistrad Tokens Type: Token Creature — Human Soldier Rarity: Common

sacrifice it unless {G} was spent to cast it

Set: HeartGold & SoulSilver: Undaunted Type: Fire Rarity: Holo Rare Retreat cost: Colorless

Set: Mercadian Masques Type: Creature — Human Spellshaper Rarity: Rare Cost: {W} {1}{W}{W}

Priest of Sheoldred

Set: Future Sight Type: Creature — Elemental Rarity: Common Cost: {2}{R} {R}

not for long

Set: Prophecy Type: Enchantment — Aura Rarity: Uncommon Cost: {2}{W}{W} Enchant creature

Set: Alara Reborn Type: Artifact Creature — Sphinx Rarity: Mythic Cost: {5}{W}{U}{B} Flying

Set: Judgment Type: Creature — Nightmare Dragon Rarity: Rare Cost: {3}{R}{R}{R} Flying

Set: Magic 2015 Type: Instant Rarity: Common Cost: {G} Target creature you control gets +1/+1 and gains hexproof until end of turn

where X is the number of creatures defending player controls