Montsey, Queen of Oozes

When Montsey, Queen of Oozes enters the field under your control, place a +1/+1 counter on all creatures and artifacts on the field.
At the beginning of your upkeep, if Montsey, Queen of Oozes
has more than 10 +1/+1 counters on it, remove all counters from all creatures and artifacts on the field.
{4}{g/u}{g/u}{t} — Double the number of +1/+1 counters on all creatures and artifacts you control.