Absolutely love stealth games. Dishonored is probably one of the better modern ones I've played.

But my I think MGS is always going to sit at or near the top of my list. Just something about the old school simplicity of it all. Plus I even had the MGS VR Missions game which was also amazing. I beat all but one level I think. I probably could have gotten it eventually had I kept practicing. It was actually quite amazing how well you had to get everything down to beat that many levels. By the end I was firing only as many bullets as was needed to kill soldiers, aiming grenades like a boss, and sticking C4 to guards backs for the simple fun of it (and for the one level which required it to take out a camera).