Inkcap, the Spore Cloud

At the beginning of your upkeep, if Inkcap is untapped, put a spore counter on it.
Remove a spore counter from Inkcap: Prevent
the next 1 damage that would be dealt to any
target this turn.
{t}, Remove all spore counters from Inkcap and
exert it: Detain each creature your opponents
control with toughness less than the number of counters removed this way.