Gnomemaster wrote:
Are there any real good resources in the pathfinder books that I could utilize?
Not in Pathfinder that I'm aware of. I believe it was in Unearthed Arcana in 3.5.
Fatigue is basically a set of temporary hit points you get when battle starts. The way we used to do it was that when combat started you took your current HP total and got that much fatigue that you could go through before you started taking actual damage. Granted we did this in a no-magic campaign world, so it was implimented as a way to make up for healing magics (we also ruled it didn't apply to energy damage, though that was rare (but brutal)), but I think giving 1/4th or 1/2 current total HP in fatigue for battles would give the sort of feel to the players you're going for.
It would also give you as the DM freedom to experiment a bit with encounters, like adding patrol of lower level mooks for the PCs to cut through (and feel badass about) on their way to taking out some spell casters set up on a ridge overlooking a battle field, or being able to throw higher powered foes at them for a bit more of a challenge.