Bolas's Citadel is a rare Legendary Artifact card from Magic: The Gathering (Magic Online Promos, PRM).
Rare
Magic Online Promos (PRM)
{3}{B}{B}{B}
Mana Value
6
Colors
B
Card Text
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.
