Survival skill FINDs terrain for Ambush; Tactics skill to best utilize it?

[Rupert]

Originally Posted by Refplace

Tracking to follow the backtrail.
Survival, Geography, and Area Knowledge I would not let help here as the first is really irrelevant and the latter two would be more used to find good areas of possible ambush in an area. However your area is limited to the trail.
Tactics is going to be the best choice to figure out the best of the possible options for setting the ambush. Then Camouflage and Stealth to hide.
Survival might be useful to help if they could use the terrain or nearby animals to help the ambush, including making some traps like deadfalls or pit traps.
Survival might help in avoiding a bad spot for an ambush. Examples would be a dry river bed if a storm is incoming, where animals might alert people of your presence, etc. I could see Survival as a safety in the first case and a complimentary to camouflage in the latter.

I would absolutely allow Area Knowledge or Naturalist (or Survival) act as complimentary skills to the Tactics check. Some parts of the trail will be better than others for an ambush, and while that's mostly tactics, knowing the area, or having a good eye for the ground helps.