DM'ing on the Fly - Hide in Shadows

So this week the party finished the ground floor of the old moat house. The finished out in the southeast corner and I stumbled across a unique situation – at least in my experience as a player or as a DM.

The party’s gnome thief/illusionist decided to reconnoiter down the southern hallway and see what he could find. He felt that he was successfully being quiet and sticking so the shadows, so he proceeded with caution. He made his way into the last room and proceeded to scout the last room. He was using is infravision to scout for enemies in the darkness – and found none.

What occurred next was a unique situation, fueled by my fleeting memories of 9th grade Biology. The gnome was searching without torch or lantern, and using his infravision to search out enemies. Unfortunately he didn’t see the giant snake – a cold-blooded creature – hidden in the rubble of the southeast corner, in the rubble of room 12. Fortunately (for the snake) it senses prey purely by heat, and readily “saw” the morsel sneaking into it’s layer.

The gnome was duly surprised by the snake, but was able to call in reinforcements. What transpired was a rather quick and uneventful fight. However, it was a good learning experience for the gnome that even a successful Move Silently and Hide in Shadows aren’t assurances of being undetected.