Jar of Poison

Whenever a creature dies, you gain 1 life and
put a fester counter on Jar of Poison.
{p/b}{p/g}, {t}, Remove all fester counters from Jar
of Poison and sacrifice it: All creatures get
-X/-X until end of turn where X is equal to the
number of fester counters removed this way.
Kodoku no Jutsu!