Amulet, Shadows, Growth
By the time you find the secret door you’re almost ready to give up and call it a day (well, a night. Can’t rob the necropolis during the day!). Maybe this tomb was never finished, this mausoleum never occupied.
Maybe it’s just a dead end! A trick. It’s been known to happen.
Besides, your lantern’s starting to sputter, the last refill of oil on your belt hanging with the weight of finality. If you waste it on a dead end then it’ll be weeks until you can scrounge up enough for another attempt, maybe months before you can sneak in again.