Generations Darkmount

I've always wondered, as a reader of Marvel Comics' G1 TransFormers comics, with all the characters available in the toyline, why did they feel the need to create new, key characters that weren't available as toys: Impactor, Emirate Xaaron, Scrounge, Spanner... and, of course, Straxus.

Or should that be Darkmount? Yes, yet again, trademark issues prevented Hasbro using the right name, but Darkmount is a suitable alternative for the first ever toy of one of Marvel's original TF Villains, since it's the name given to his base of operations in the comics. Considering that Straxus was only seen to transform once, and turned into some kind of wierd flying cannon - vaguely similar to Galvatron in some ways - what sort of alternate mode does he get for his first toy?