Or any third installment in any of their games: HL3, L4D3, TF3, Portal 3, DOTA3

Counter Strike had more than a third installment and HL got two episodes and a prequel.

Counter-Strike 2 and Ricochet 2 first.

Didn't the spiritual successor Back 4 Blood release not too long ago? No good?

The steam reviews are mixed, compared to overwhelmingly positive for L4D2. It's also Windows exclusive with Easy Anti-Cheat so it can't run on Linux. (It's a coop game, who cares about cheating there??)

Cheats can also be used to grief other players in the match making queue.

B4B does have a human vs zombie multiplayer mode

However, that mode is nothing like the versus mode people actually wanted.

I haven't played it, but this video gives the impression that it is much less polished in comparison to its predecessors. However it could just be nitpicking. https://www.youtube.com/watch?v=EdRLNUGmFC8

I would recommend giving this video a watch. It'll show you just how much care and attention to detail was put into L4D 1 and 2: https://www.youtube.com/watch?v=EdRLNUGmFC8

It's okay. The difficulty ramp-up is really steep to the point where once you finish the easier difficulties it just gets way too hard. Maybe if you play with friends it would be different, but I was mostly solo queueing.

That being said... it was a lot of fun until I got frustrated with it! It's on the PC game pass.

Didn't know it existed you just made my weekend.

its not as good.