The Cabin Of Leeches

At the beginning of your upkeep, add {b}{g} to your mana pool.
1{b}{b}: Create a 1/1 Black Leech creature token with Deathtouch.
{1}{g}{g}: Create a 1/1 Green Leech creature token with Reach.
{3}{b}{g}: All Leeches get +2/+2, Lifelink, Wither, and Trample until end of turn.
{4}{b}{b}{g}{g}, {t}: Create an 8/8 Black Leech creature token with Deathtouch, and Trample.