The Sigil System Stealth Mod

Publisher's blurb: The stealth rules are all very simple and is based around the Awareness Scale, which serves to turn whatever compound (be it a castle, a bank, a star ship) into an entity against which you are competing with to remain hidden. The Awareness Scale represents the compound's mood and allow the GM to have the NPCs inside the compound react accordingly to what you, the player, is doing. As to what the player is doing, they'll be trying to raise hell as quietly as possible, while their actions (both narrative and through Skill Checks) will raise their Awareness Level along the Scale, while time and the use of the Sigils meta-currency hope to bring it back down. If you've ever wanted to try your luck and skills at sneaking through an entire area, skulking around where you shouldn't be, and taking down enemies before they reach you, well we got the Mod for you.