Pool Nation
Won all the cups and beat all the challenges (298/298 stars), and since there's not much else to do in single player, I consider the game beaten. As far as pool sims go, this one is probably the best I know of. The ball physics feel realistic, and the robust system enables the use of all sorts of trickshots, such as jumping and knife edges which I don't think are possible in all pool games. The trickshots are very fun to shoot, and the optional challenges (like, "pull off a jump and a swerve shot on a frame") in each match make them a little bit more interesting, instead of being basic pool matches after one and another with the only goal being to win the match. While the pool itself is, in my opinion, pretty much perfect, the opponents could've been fleshed out a little: now they're basically faceless clones with only a mugshot to separate them from each other. It would've been cool if they had had personalities and such (like, becoming nervous if they see the opponent getting a streak, thus making mistakes themselves, or something). They all felt the same: they're invisible beings, pocketing balls until evidently failing (no-one ever did an 8 or a 9 ball streak), depending on their difficulty level. And I also disliked the music. It sounds very stock and not at all catchy, one song even being a solo piano performance that sounds a lot like a lullaby for babies. Sometimes the music would also "break" (songs stopping all of a sudden), so the audio department certainly could've used a lot more work. But anyway, like I said, the actual game of pool is done very well and that's what matters the most.