Necroshade

{t}: Add {b} to your mana pool.
{1}{t}: Sacrifice Necroshade: Search your library and graveyard for a Skeleton card, reveal it, then put it into your hand. Then shuffle your library
{5}{b}{b}{b}{t}: Sacrifice Necroshade: All Skeletons you control get 3 +1/+1 counters. You may then play a Skeleton card from your hand without paying it's mana cost.