Boletaria's ruin

Boletaria's Ruin comes into play with five
soul counters on it.
Whenever a creature is killed by a demon
remove a soul counter, soul counters may
only be removed this way
When Boletaria's Ruin has no more counters
on it, sacrifice it and put five +1/+1 counters
on all demons on the battlefield and destroy
all non-demons.