honorable mentions:
some of my all-time favorite games that i'm not going to constantly keep on the listtribes 2
planetside 2
world of warcraft, ffxi, ultima online //i grew up on the internet, chatting in active worlds and palace chat, and ultima online was my first mmorpg when i was 12 years old
guild wars 1 and 2 //i didn't actually play a whole lot of guild wars 1, but i got into the sequel in a big way, almost exclusively playing the wvw pvp mode for a couple years
titanfall 2
destruction derby (1995) and more recently: wreckfest
divinity original sin 2 //beating this on tactician is one of my favorite achievements
final fantasy tactics