I am not a frequent gamer; I've never owned a game system or bought any non-educational games. Even so, I was thrilled when "The Eternity Clock" finally came out for PC. After all, what Whovian wouldn't be thrilled at the prospect of running around as River and Eleven?
The mechanics are good, easy to understand even if you're using a keyboard for controls. The graphics are smooth and of good quality. There were one or two points where the character froze and refused to move, as well as a moment of green tinting while escaping Stormcage when the trap lights affected the whole screen. I also have to log off via task manager, but that might just be me. The audio can be controlled, setting it louder or quieter, with subtitles as an option as well.
In single-player format, one switches between playing as the Doctor and as River. At first, one plays as the Doctor trying to escape the London Bank, but it switches to River in Stormcage. After she joins him, she becomes a NPC and the user plays the Doctor. The main difference between the two is that the Doctor uses his sonic, while River takes a more aggressive approach with her lipstick and gun.
It's a really fun game to play. I enjoyed breaking out of Stormcage, even if the method of disabling guards (the hallucinogenic lipstick) resulted in such thoughts as "stop running around and let me kiss you!" I'm also a Doctor/River shipper, and enjoyed some feels from the scenes with them together. I could just imagine River making sarcastic comments when I made a mistake controlling the Doctor: "Sweetie, why are you impersonating a gibbon?" or "Stop running around and give me a boast. I hate you sometimes."
It's only $10, which seems a reasonable price to me. Here's the US link.