I don’t know how I missed this rather amusing review of Trail of Cthulhu on I Pants The Dwarf.
There’s one other thing that Trail of Cthulhu changed out, and it’s not only a doozy, it’s the game’s saving grace and the number one reason you should try this version.
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Each high-level being is described in terms of the mythos, and then numerous suggestions and interpretations of what the being is, sometimes in terms of conventional science and magic, sometimes not even that well nailed down. The GM can pick, choose, and mix his own, keeping the investigators in the dark and on their toes until the time of the reveal.