The others have such a strong place in my heart that not including them here would feel wrong, but Civilization IV and Minecraft are less certain choices. I think I have to include Minecraft though, and I suppose Civilization also opened up another world for me, even if I don't exactly play a ton of 4X games - but that's due to lack of time rather than interest.
Some other contenders for the last place were Alan Wake and Oblivion, Alan Wake for being a particularly memorable experience and Oblivion for being the first proper open world experience for me, but I don't think either had much more effect on me than 'just' impressing me. I also briefly considered the first Assassin's Creed and even Dynasty Warriors 2, because for the longest time it was one of my favourite seriesm, but I don't think their effect on me is otherwise notable enough to include in any of the limited slots.
