Vision and Observation skill first mention v1c8 & v2c1.
Various observation skills exists for certain classes v1c8
Like discovering a hidden entrance for thieves
LIke tracking skill for rangers and hunters.
Special vision skill
Vision (Archer class): Skill may be applicable to other classes.
Large field of vision (source ?)
Observation (Archer class): Skill may be applicable to other classes.
visual tracking skill ??? (source ?)