Persona Q: Shadow of the Labyrinth.
UNBELIEVABLY complicated and fairly difficult. I wish I had a walkthrough for it.
It has had it's AWESOME moment though...
Dude, be ready for a very, very
annoying final boss battle. Make sure you have Agidyne, Bufudyne, Ziodyne and Garudyne somewhere in your party, as well as the ultimate buffing and debuffing moves Heat Riser and Debilitate. You're gonna need those moves, as well as some binding moves. I found the move Makajam particularly useful in the second part of the final battle.
Anyway, games I'm playing right now, lets see what I have.
Persona Q: Shadow of the Labyrinth (P4 storyline, since I finished the P3 storyline)
Legend of Zelda: Majora's Mask 3D
Sword Art Online: Hollow Fragment
Super Smash Bros. 3D
The World Ends With You