This post came to mind after I played the new MW3 campaign. For me personally it has to be Wolfenstein: Youngblood. That game was a complete disappointment compared to the rest of the new Wolfenstein games. The only reason I ended up finishing the game was because my friend and I were playing it together and decided to tough it out and see the end of the story. Gears of War: Judgement is another dishonorable mention. A game that I did not like at all, but continued to finish it solely because I had played every other game in the series so far.
Diablo 4, can’t think of anything worse I’ve beaten in 20 years. It really was insultingly bad and I’m ashamed of myself for buying it.
I just don’t get how they could spend 6 years and hundreds of millions of dollars to downgrade the gameplay from diablo 2 - a 20 year old game and diablo 3 - a 10 year old game. It doesn’t even have loot, they removed all the varieties of loot from previous games and only left uniques - but they only drop after you’ve beaten the game and are so rare you’ll never see one.