Editing Open4E:Skills (section)

===Perception===
Perception is used to examine your surroundings, spot hidden things, and detect unusual sounds, odors or tastes. Your Perception check also determines your Spot defense value; your Spot is equal to your Perception check + 10. Your Perception skill check is based on your Wisdom modifier.

=====Search Area=====
* (At-will minor action * basic skill saving throw)
* Target:	One square within a distance of twice your Wisdom modifier that you can see.
* Check:	Perception vs. any Stealth check results or Spot DC’s
* Effect:	You notice any hidden creature, item or detail within a number of squares around the target square equal to your Wisdom modifier for which your saving throw exceeds that detail’s Spot DC or Stealth check value.