Haven’t played as many games as the rest of you but the ones that stand out for me are...
Dead Space 2 - probably my favorite game of all-time.
The Last of Us - so far, THE best game I’ve ever played.
Rock Band 3/4 - they did Guitar Hero and RB 1/2 released before this decade but what Harmonix did with RB was merge karaoke and party game in a manner i just couldn’t get enough of. Probably the game(s) I’ve put the most hours into and STILL have friends over to play.
Portal 2 - my favorite coop experience.