Barney & The Bears

Barney & The Bears enters the battlefield with 6 stun counters on it unless you control 3 or more bears,
It gains +1/+2 for each bear you control.
{t} Search your library for a Bear, put it onto the battlefield untapped.
{1}{t} Exile target artifact opponent controls.
End step - Put a stun counter on Barney & The Bears
if you didn't attack this turn.