When the Barbaric Machine Beasts became too big for the Go-ongers to handle in human form, their Engine buddies from the Machine World are called upon to form Engine-O in order to defeat the enlarged monsters. This fun set contains three Engines (Engine Speedor, Engine Bus-on, and Engine Bearrv), each with its own unique feature: Engine Speedor's wings can be deployed, Engine Bus-on has a compartment for storing Engine-O's Go-on Sword, and Engine Bearrv's body is movable. All three Engines can be combined to form Engine-O, armed with its Go-on Sword and wielding a shield formed from Engine Bearrv's lower body. The included Engine Speedor's Engine Soul can be inserted into Engine Speedor to play its phrases. Engine Souls of Bus-on and Bearrv from Self Henkeijuu MantanGun and DX Highway Buster Set respectively can be inserted into their own Engines to play their phrases. Three test button batteries are included.