I am unclear from the tooltip of level 5 Detect Hidden if it's required for you to open secret doors, or just a useful aid in helping you find them.
I ask because I found 4 of 5 lorestones in the Gorguath runes. I could see the last one up above the room where you fight the Thresh, but couldn't figure out how to get to it. Looking around online for the answer, I saw that you apparently need to go through a secret door to get the one I'm missing. However, I've run around the dungeon like crazy trying to interact with walls and such hoping I'd be able to open a secret door, but have had no luck, making me wonder if it's even possible to open the secret door without the skill.
Best Answer
Yes, you do need it.
You are unable to interact with Hidden Doors until you are at least level 5 in Detect Hidden.