Below is a list of all the available elements in the Transportation group in Doodle God across all 4 episodes.

Episode 1:
Airplane
Boat
Car
Cart
Chariot
Frigate
Locomotive
Ship
Steamship
Wheel

Episode 2:
Airplane
Boat
Car
Cart
Chariot
Frigate
Locomotive
Ship
Steamship
Wheel

Episode 3:
Airplane
Boat
Car
Cart
Chariot
Frigate
Locomotive
Ship
Steamship
Wheel

Episode 4:
Transportation element group is not available in episode 4.