Haunted Market Square

{t}: Add {b}.
{t}: Add one mana of any color to your mana
pool. Use this mana only to cast Adventurers.
(Adventurers are creatures with the subtype Warrior, Rogue, Wizard, Monk, and/or Cleric.)
When you control three or more adventurers, sacrifice Haunted Market Square. You get a
Treasure token, draw a card, and gain 2 life.