Final Fantasy Type 0 HD
Tales of Zestiria
Omega Quintet
Rogue Galaxy
Atelier Ayesha Plus
Ar Nosurge Plus: Ode to and Unborn Star
Hyperdevotion Noire: Goddess Black Heart
Persona 4 Golden
Ys: Memories of Celceta

I finished 20 games in 2015, of which 15 were new games I had never before completed so I'll pick from those.

5. DMC: Devil May Cry: Underappreciated game from Ninja Theory. The series fans threw a fit with the new design of Dante, but the game is still a lot of fun and the level design is excellent.
4. Tales of Xillia: The Tales series is finally gaining some traction in the west which is a great thing for JRPG fans. Not the best game in the series, but a thoroughly enjoyable experience nonetheless, with a good cast and an interesting, if slightly cliched story.
3. Portal 2: I know, I know. I'm late to the party with this one, but better late than never. Portal 2 is every bit as good as its reputation says. I'm really glad I finally got around to this one.
2. Metal Gear Solid 3: Snake Eater: Again, I know. Late to the party and all that. While others were busy getting hyped with Phantom Pain, I was enjoying playing through the earlier games in the series for the first time. Snake Eater is so far my favourite in the series.
1. The Legend of Heroes: Trails in the Sky: The best game I played all year, and one of the best RPG's I've ever played. The character, story, music and gameplay are all absolutely brilliant. Easily among the best experiences I've ever had playing video games.