Widowmaker

Ultimate: Infra-Sight - (Widowmaker enters the battlefield with X charge counters on her. At the beginning of your upkeep, remove a charge counter, then, when the last is removed, put X -1/-1 counters on up to X target creatures, their controller gets X poison counters then place three charge counters on Widowmaker.)
{g}{b}, {t}: Venom Mine (Target creature gains infect until the end of turn.)