This game is incredibly well put together! Every asset is of really high quality, and the lighting helps sell the mood in such a convincing way. The mechanic of hiding and traversing using vents is simple to understand and execute.
Though I felt the stealth was fun, I found that as a dominant strategy it was much easier to simply run through getting seen by every Orc, only to hide or use the smoke bomb once an armor piece was in sight.
I found it humorous that the Orcs couldn't find me even if I hid right in front of them, but either making them check cover or having some additional hazards that could slow your movement for a time might mitigate this and prevent wanton sprinting.
Regardless, excellent work!