Untethered Express
Untethered Express {4}
Artifact - Vehicle | Power/Toughness: 4 / 4
Trample
Whenever Untethered Express attacks, put a +1/+1 counter on it.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)
Latest set: [AER] Aether Revolt ( U · #179 )