Day 23 - Game you think had the best graphics or art style.
I'm going to split this by system. This isn't everything, but it's off the top of my head at the moment.
Saturn - Panzer Dragoon Saga
DS - 999
PSP - KH:BBS
PS2 - Dirge of Cerberus, KH2
PS3 - Metal Gear Solid 4 (overall graphics), Catherine (art style)
PS2 - .hack//G.U. series for art style
PS3 - Resonance of Fate, Castlevania: Lords of Shadow, and FFXIII specifically for backgrounds
DS - Hotel Dusk, Last Window, and the Ace Attorney series for art style
PSP - Crisis Core for overall graphics