Perception

This root skill is used to add to your awareness ability. It is like having eyes in the back of your head. This skill works off of your environment as you perform other actions. For example while in combat you catch a glimmer of light reflecting off the person in a mirror, or see his shadow before he releases his arrow at you. Being aware allows you to keep your agility bonus to defense vs that attack. this is not a good skill to use vs a skills sneak.

The difficulty of the roll is based on environmental factors:

Range of a attack can also play into the difficulty.

Addional Modifiers such as weather conditions and combat conditions can modify the difficult as well; heavy rain, fog, and various spells and effects.