Countdown to Extintion

When Countdown to Extintion enters the Battlefield, put 4 extintion counters on it.
At the beginning or your upkeep, remove an extintion counter.
When you remove the last extintion counter, target player destroys the creature under his or
her control with the highest power and you put
4 extintion counters on this carg again.
We dance like marionettes, swaying to the Symphony
of destruction.