Shadows of Eidolon is a classic bite-sized romp through some pitch black sewer tunnels. For the most part it is pretty enjoyable. The mapping is pretty basic but the linearity of it helps avoid getting lost in any of the pitchblack areas. To help see, the normal blackjack is replaced with a permanent effect default Thief flare. This single object does double duty for most of the mission, providing both a tense atmosphere with it's measly radius of light, and helping hide some of the cruder edges of the map.

There is very little story present and what is there is nothing any Thief fan hasn't seen before. Still though, I'd recommend spending the 30 minutes max it takes to complete this mission when in the mood for something new and something very literally dark.