Melee configuration. The transformation gimmick is omitted for the equipping of what I call the Overhead Weapons System (creative, I know), but the legs can still turn into claws. That's a one-time cast-off thing, though.
Aaaand full armour mode:
Swords and cannon, plus the beam rifle/spear thing the Gabthley originally comes with, and a gatling gun for good measure.
It's called the Overhead Weapons System because it's a weapons system that goes overhead. Duh.
Of COURSE it flips around so all the guns can be fired at the same time.
Edit: Added that one Astray gun-sword-thing that came with a magazine some time ago.