I've thought long and hard on this. It's gotta be Mordins death in Mass Effect 3. The way he mumble-sings the song he sang in the second game. the lead up to it. Got it was just amazing! It almost made up for the terrible ending for me.... Almost...
Just one thing. Beards are AWESOME! =D But seriously, Geralt doesn't look old in the pics of W3 I've seen he just looks like he doesn't care what he looks like anymore. (Which i actually like.)