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I just beat the game with all 7 treasures and I'm a bit disappointed...there doesn't seem to be any sort of award aside from the satisfaction that comes with finding them. I'm aware that there's a Steam achievement, though I purchased Grimrock from GOG so I don't have access to those (nor do I really care about them). You'd think after all the work they'd at least unlock some sort of extra little scene at the end or at least some equipment in the game itself.