This afternoon I went down to my local HobbyCraft store and had a very successful trip: I picked up a couple of model kits in a clearance sale that should help me build the Warmonger's primary weapons: the battery of eight deathstrike missiles, and the vengeance cannon.
One of the kits was a simple snap-fit model of the ARC Starfighter from the Star Wars movies. The engine pods attached to the barrel of the plasma annihilator make an exceedingly evil-looking weapon:
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I also found a kit of an Apache helicopter that has the right number of missiles to make up the deathstrike battery: I'm scratchbuilding the mount for this weapon from plastic tubing and I-bar: but I'll save that for a future update :)
So far I'm really impressed with the razor saw: it makes a whole range of very delicate cuts very simple indeed. I recommend you get yourself one.