Untethered Express (AER) from Aether Revolt, available at 401 Games Canada.

• Rarity: Uncommon
• Finish: Normal
• Artist: James Ryman
• Card Text:
  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.)