We've got two conflicting sources regarding Prime's combined mode with his trailer: 1-"Butterfly Prime"-as evidenced by the Ultimate Prime toy, Optimus has a power-up mode with armor provided by his trailer. He has the one MechTech cannon and no other discernible weapons. 2-"Jetwing Prime"-The retooled ROTF Leader Prime from Takara, this Prime seems closest to what's been seen in the trailers: Prime has two massive jet boosters (likely from Jetfire) and two equally massive canons. This toy does not, however, show any evidence of an armored, power-up mode. Both toys do seem to overlap in some areas, yet are divergent in others. Ultimate Prime has wings and some sort of bizarre array protruding from the trailer behind his head. Jetwing Prime has wings as well. However, Ultimate Prime doesn't seem to feature the boosters nor the massive guns. So which version is closest to the film version? Or will the film version be some sort of amalgam of the two? I personally think the trailer simply holds Prime's Jetwing parts: boosters, wings, and canons. It seems the Ultimate Prime is a case of wasting no plastic, thereby creating a film-inaccurate trailer-armor combined mode. If anyone knows for sure (from the novelization or comic book adaptation), please be sure to use spoiler code.