Unstable Servotitan

Vanishing 1 (This creature enters the battlefield with
one time counters on it. At the beginning of your
upkeep, remove a time counter from it. When the last
is removed, sacrifice it.)

Unstable Servotitan's power and toughness are
equal to the number of time counters on it.

When Unstable Servotitan enters, time travel X
times.