Unstable Terrain

Unstable Terrain indicates ground that moves or shifts unpredictably underfoot. Unstable terrain usually requires a Balance check to maintain your footing. If you fail the check, you fall Prone. Additionally, Tumble and Stealth checks suffer a -4 penalty in in Unstable Terrain.

The difficulty of the Balance check is dependent on how readily the terrain will shift (sample difficulties listed below). Moving hastily through Unstable Terrain (ie. Sprint Speed) increases the difficulty by 1. Overland movement over Unstable Terrain is difficult, and usually reduces overland movement speeds by half. Every phase you spend traveling over Unstable Terrain forces you to make a DC 10 Resilience check or gain 1 point of Fatigue.