Colossal Plow [Kamigawa: Neon Dynasty Commander]

Whenever Colossal Plow attacks, add {W}{W}{W} and you gain 3 life. Until end of turn, you don't lose this mana as steps and phases end.
Crew 6 (Tap any number of creatures you control with total power 6 or more: This Vehicle becomes an artifact creature until end of turn.)