Wall of Stonks

When Wall of Stonks comes into play put a
Stonk counter on up to X creatures you control.
At the beginning of your upkeep put a Stonk
counter on each creature you control with a
Stonk counter on it.
When Wall of Stonks leaves play remove all
Stonks counters from all creatures you control
and then each opponent mills cards equal to the
total amount of Stonk counters removed this way.
{x}{u}{u}, Sacrifice Wall of Stonks: Each
opponent mills X cards.