Abilities Questions

What does the spy ability do? It is not a hero ability, just a basic one. I can't tell that it does anything.

Also, can you get wander to work on a neutral hostile creature? I tried it, but the guy didn't move.

Also, what about the revenge ability.
Somebody should make a list of all the abilities and what they do. I might work on it if i could ever finish the map I am working on.