This requires 2 people in an online Co-Op match. One person must get a helicopter from the Agency Tower and the other must get a vehicle (Agency Supercar or Cruiser. Both players should meet at the stunt ring. Equip Mag Grenades and stick one to the bottom of the helicopter and one to the roof of the car. Use the helicopter to fly the car through a stunt ring. Be careful: The mag grenades have a timer on them and will eventually explode.

You can also toss a car with a fellow player inside through a ring.