Vio, Selesnyan Knight

Teamwork.
Whenever played on the battlefield, Miran, the
Ledev Wolf is also placed on the battlefield. The
first time Vio, Selesnyan Knight attacks on your
turn, both Vio, Selesnyan Knight and Miran, the
Ledev Wolf gain a +1/+1 counter.
{t}{w}{g}: Target creature is given Defender
ability until the end of your next turn.
(A creature with defender can't attack.)