NBA 2K17Unobtainables are arguably the worst thing that could ever happen to an achievement hunter. It's damn near why I nearly put Watch_Dogs 2 on this list, beacause I have 960G in that game and one of the story mission achievements has glitched so that I probably will never get it and it will always say 96% next to the name on my achievement list which just grinds my gears. NBA 2K17 was obviously developed by someone who had a bad experience with an achievement hunter because this game is just there to annoy those who have played it. The story mode (which is fantastic by the way) is missing parts of it which relate to achievements such as a part where the coach is meant to give you a gift, I never even saw this part and I finished the story mode. This is a common theme throughout. Not only that but if you are looking to 1000G this game then you may aswell give up now because it's going to take an inhuman amount of skill to get all the achievements due to the online achievements being over the top hard.
Halo: The Masterchief Collection4000G!! and with DLC 6000G!!! It's enough to make any hunter froth at the mouth but they should look turn away as disappointment ensues. Not only does this contain many achievements that relate back to completing the game on the hardest difficulty, there are ones relating to doing levels with certain scores and a certain time. Not only all this but there is the infamous achievement where you need 3 other friends and to finish a level whilst using only a Ghost ship. Crazy. Absolutely crazy.
Gears of War 4If you're a completionist just dont even go anywhere near this game. Seriously 4.0 will absolutely destroy your life, it has nothing to do with a ridiculous amount of kills anymore. No, that was deemed too easy by Coalition. Now you have to do everything there basically is to be done in the game. Including, collecting every ribbon on the game which requires a decent level of skill online, completing horde in one setting on numerous occasions, finishing the campaign on insane. It's just an absolute nightmare of an achievement, this will take 500+ hours just for ONE achievement.
ChromehoundsWhat happens when you pick up a game from around the launch title of the xbox 360 that was heavily multiplayer focused and developers weren't familar with how achievements work yet? You get Chromehounds. There is only 160G available for offer here because the rest of the G is tied up in multiplayer achievements that are hidden behind closed servers. There to be never unlocked again so if you have gotten any of these achievements then count yourself lucky. And I'm not going to start the whole debate about whether developers should include multiplayer achievements in games that are at some point going to be closed or will never have the player base to gain a decent community online.
Assassins Creed: UnityThis list isn't all that hard if you're willing to put alot of time towards it. The only problem with this is that you will actually have to play this game in order to unlock any of the achevements and I would recommend that NO ONE goes to play this mess of a game. It's broken, unplayable and boring. Just avoid this game whether you're an achievement hunter or not.