Strike From Ambush

It's nothing new, or different, but it has proven effective on occasion: you lead your pack to this one spot on the way to a small treasure room where are ledges above the walls, hidden in the shadows of the ceiling. You help each other climb up to the ledges, which sometimes spawn small treasures that are supposed to reward 'heroes' who search the dungeon thoroughly but almost no one knows are there, or cares if they do know, since the rewards are so piffling compared to the effort.

You wait, seconds turning into minutes, minutes into hours, and then...