One of the orcs worst enemies are the outlanders who can just be chameleoned in hordes and attack, flee and then chameleon again. The orcs are wiley and naturally warey creatures from lives of violence and so could possibly have an ability to sense attacks from the shadows similar to the legacy but perhaps a diluted version. Alternatively they could, when engaged in fighting release a smell from a gland on their body to allow them to locate the camo/chameleon/hidden person until it wears off so that they could reengage or know if they are still lurking about.

Again, just an idea.

-----Abernyte

Detect rangers etc. in terrains in which they can hide. This was announced a month or two ago and you might or might not have missed it.

Generally, I'm inclined to wait a bit and see how that shakes out before doing too much more with orcs vs. stealth classes. I could see orcs thematically having an ability along the lines you describe but I'm not sure right now if they still really need it or not.

Orcs could not see my ranger in caves. At the very least. I didn't try swamps, so I am not sure here.
On the other hand, my ranger could not see hidden orcs in caves as well (and caves were his natural terrain).

I am 95% positive of that. So I think something is not coded here.

I'm not really awake enough to try to explain how this works to you right now.