The Rutile Twins

Quadruple Strike
Whenever this creature becomes tapped, put a +1/+1 counter on it.
Exile the nontoken Rutile Twins: Create two Copies
of the Rutile Twins. It has Double Strike and is a
1/3. They get a number of +1/+1 counters equal to
half the number of counters removed from it.
Exile Both Rutile Twins: Return the Rutile Twins
from Exile to the Battlefield, and put a number of
+1/+1 Counters on it equal to the total number of counters on it.