Rishcall, Ever Growing

Vigilance
Shed Skin — {t}, Sacrifice a mutation on
Rishcall, Ever Growing: Add X +1/+1
counters equal to the mana value of the
sacrificed mutation.
{g/u}{g/u}, Remove all +1/+1 counters from
Rishcall, Ever Growing:
Regenerate Rishcall, Ever Growing.