Oh, have we taken account Tamuz (http://wiki.white-wolf.com/exalted/index.php?title=Characters:Tamuz)? He may be guy who could oppose solar circle greatly or aid it greatly.<br/><br/>Anyways while writing I checked Chiaroscuro and noticed themselves they have quite formidable defenses....so it needs rather massive attack by abyssals to overcome it. So the battle will be rather massive and there must be something going on preventing first age essence cannons not peppering undead away (or simply there is too many of them compared to number of cannons, perhaps abyssal siege weapon which deflects essence shots).