Fallout 4 No. 1 for me. I've been off it a couple of months catching up with other stuff, but it occupied my attention for 4 - 5 months solid after purchase.
GTA V - Just finished my second playthrough of the SP game (MP not of interest). It really is a microcosm of LA and SoCal, one of the most lifelike looking games out there. Huge improvement on GTA IV (which no longer runs on Win 10 for me anyway).
Deus Ex HR - The Director's Cut is brilliant and while not so long to play through as some of the other titles is atmospheric and absorbing, with many different play styles and alternate endings.
Skyrim - Obviously in the same genre as FO4 but with a medieval/fantasy setting. Graphics still look good and will keep you going for weeks if you seek out all the factions and side missions.
Saints Row The Third - Scrapes in as a 2011 title. Kind of the altGTA but I found it very entertaining and good fun.
Also rans: Mass Effect 2/3, Euro Truck Sim 2 (also American Truck sim) plus a few others I can't recall without looking at my lists.
GTA V - Just finished my second playthrough of the SP game (MP not of interest). It really is a microcosm of LA and SoCal, one of the most lifelike looking games out there. Huge improvement on GTA IV (which no longer runs on Win 10 for me anyway).
Deus Ex HR - The Director's Cut is brilliant and while not so long to play through as some of the other titles is atmospheric and absorbing, with many different play styles and alternate endings.
Skyrim - Obviously in the same genre as FO4 but with a medieval/fantasy setting. Graphics still look good and will keep you going for weeks if you seek out all the factions and side missions.
Saints Row The Third - Scrapes in as a 2011 title. Kind of the altGTA but I found it very entertaining and good fun.
Also rans: Mass Effect 2/3, Euro Truck Sim 2 (also American Truck sim) plus a few others I can't recall without looking at my lists.