A character is hidden from those who don’t know his location. They may not attack him nor target him with skill checks that require line of sight. When a hidden character attacks an oblivious target within Close Quarters (30 ft.), the target is considered Flat-Footed.
Any character aware of a hidden character’s presence may make a full-round Search check vs. the hidden character’s Blend or Sneak (GM’s choice), and with success the target character loses the hidden condition. A character also loses this condition whenever he casts a spell, makes an attack, or takes any obvious action.