Unstable Crystal Anomaly

Indestructable. All creatures get -1/-1.
Whenever you cast a creature spell, put X charge
counters on Unstable Crystal Anomaly, where
X is equal to the creature's power.
If Unstable Crystal Anomaly has 100 or more
charge counters on it, you get protection from
green until end of turn, then remove all counters
from Unstable Crystal Anomaly and it deals 100
damage to each player, creature and planeswalker.