My favorite games of the decades. Bolded are my favorites from each year:
2010: Mass Effect 2, Bioshock 2, Alan Wake
2011: Dead Space 2, Dragon Age 2, L.A. Noire, Uncharted 3
2012: Deus Ex: Human Revolution, Diablo III, Dragon's Dogma, Persona 4 Golden (my personal game of the decade), Darksiders II, FTL, Borderlands II, Dishonored, The Walking Dead
2013: Luigi's Mansion, Bioshock Infinite, XCOM, The Last of Us, GTA V, AC: Black Flag
2014: Bravely Default, Danganronpa, Stick of Truth, Wolfenstein, Watch Dogs, Divinity: Original Sin, The Wolf Among Us, The Walking Dead Season 2, Alien Isolation, Far Cry 4
2015: Dying Light, Bloodborne, Witcher 3, Until Dawn, Wasteland 2: Director's Cut, Life is Strange, Tales from the Borderlands, Rise of the Tomb Raider, Game of Thrones (Telltale)
2016: Firewatch, I Am Setsuna, Uncharted 4, Deus Ex: Mankind Divided
2017: Resident Evil 7, Horizon: Zero Dawn, Nier: Automata, Sexy Brutale, Prey, Pyre, Cuphead, Battle Chasers: Nightwar, The Evil Within 2, AC: Origins, Wolfenstein II, DOOM, Xenoblade Chronicles II
2018: God of War, Frostpunk, Moonlighter, Dead Cells, Monster Hunter World, Return of the Obra Dinn, Call of Cthulhu
Man. 2010-2013 produced some insane stuff. Lots of instant classics out of those years.
I imagine it's gonna come down to Skyrim, Portal, RDR or the Witcher. If I had to pick out of those I'd probably take Witcher.