They really shouln't have shouted.Orcs are not massively bright creatures, but even they know that when the Master has told them to patrol an area, it means to check out any shouts and strange flashes of light.
Kolg and Gruk had been hastening back to camp when the sounds of "man-folk" voices had attracted them. Evidently a fairly large party, too -- too large for two lone orcs. So Kolg had run, run like a Kyrin, back to the post at the mouth of the diggings for reinforcements, while Gruk had continued to track the man-things. And while an orc-captain had dutifully scrawled a report ("MAn-peple mving in udregraownd plase") for Shadow Demon to hand to Venger, a detatchment of twelve orcs was c r e e p i n g u p on our friends...
"Aiya! Uruksh! Uruksh!" Arrows began to clattter and fly toward the Young Ones, and four orcs armed with broad, stabbing blades, sprang out of the darkness and attacked the Adventurers!