Test of Nature

Test of Nature enters the battlefield with 1 Control counter.
{x}{1}{r}{g}: Give target creature -X/-X until end of turn. If the creature survived it gets +X/+X and add a Control counter on to Test of Nature if X was equal or higher than the amount of Control counters on Test of Nature. If the creature died due to this effect remove X control counters off of Test of Nature.
Whenever Test of Nature has no Control counters on it its controller takes 5 damage and Test of Nature is sacrificed.