Tears of the Kingdom without a doubt so far. Enjoyed every second of it.
Honorable mentions are Hi-Fi Rush, RE4 Remake, Diablo 4 - even Jedi Survivor (especially if it didn't run like shit).
And I fully expect Starfield, Spiderman 2, and Baldur's Gate 3 to give TOTK a run for its money. Honestly a great year for gaming despite some shitty PC ports.
100% TOTK
I haven't played many games that have came out this year, so Pizza Tower wins by default. I may pick up TotK sometime in the future if I can get it used or on sale, but for now I don't really intend on playing it, especially not at full price.
However, my favorite game that I've discovered this year has definitely been Ultrakill. Its the most fun FPS game I've played (not saying much, since most FPS games are pretty terrible nowadays, but still its a really good game).
I purchased it in november last year so it's technically not 2023 but I have to give it a mention because it's been receiving massive high quality updates ever since and it's one of my favorite games atm - Against the Storm. Really charming and well designed, stable without any major bugs, active communicative devs... It's an indie game done right.
TotK for sure. I'm expecting Armored Core 6 to be my answer for the second half of the year; FromSoft has just been consistently so good.
Kingdom Come: Deliverance.
Stay patient dudes.
Toss-up between Street Fighter 6 and Diablo 4!
Both are excellent, really. No game is perfect but I've enjoyed my time with these two so far.
My ROG Ally arrived earlier this week as well, and I gotta say, being to play these games in handheld form ups the novelty a bit - leading to even more playtime.
I've been LOVING SF6. It's the first fighting game that has ever truly clicked with me.
I really need to pick up Diablo 4, but I'm spoiled by Diablo 3 on the Switch for portable play while my wife watches TV. I'd love to get D4 on the Steam Deck, but the setup seems a bit intimidating, and I'd worry that future updates would break it.
Yeah I've installed Bnet on the Steam Deck using Lutris and I agree it's not a very intuitive process. Lutris does its best but there are still some things you will have to look up.
There's another script that's rising in popularity, NonSteamLaunchers, which aims to automate this process for you. I haven't tried it but the people who have, have said that it's easy. I'd suggest giving it a try.
D4 on gamepad is VERY playable. I'm glad Blizzard learned from their experience of releasing D3 on consoles and implemented those on D4. Obviously MnK is still faster for some actions, particularly inventory management, but you can really play the game without feeling like you're hampering yourself.