-Halo 2
Amazing story, epic and emotional tone, the arbiter was a great addition, and the anniversary has by far the best graphics of any halo game.
-Halo reach
In my opinion this is the campaign with the least issues, great story with a perfect tone, and having your spartan as the main character is neat. The only reason it’s number 2 is because halo 2 has a lot more greatness. And since I’m not a lore -Yoink!-, I don’t care that it contradicts the books 
-Halo Combat Evolved
A true classic with much replayability, and by far the best gameplay of any halo game ever (feels a lot like half life to me)
-Halo 4
By far the best story next to halo 2, the most emotion we’ve seen in any halo game, and if you didn’t cry during cortana’s death then you’re a monster. The story does have flaws, for example te didact wasn’t terrible but rather underused. Unfortunately the gameplay of the campaign sucks sangheili cloaca, the level design is repetitive and linear. There are a few missions i like, composer was definitely my favorite. But besides that aspect, halo 4 is amazing.
-Halo 3
Halo 3 is not good, not bad but not good. The game is epic don’t get me wrong, but that’s all it is. There are so many plot holes in the game that it distracts me. For example: apparantly Sargeant Johnson was just HANDED the forward onto dawn and goes ALONE on this big ship when the game could of just had him get there from a pelican. The story is fun but it has too much wrong that i notice that it can’t be excused.
-Halo wars 2
An average story with gameplay that is not very fun, but that’s more because I’m not a fan of RTS games. The game is okay, but the game seems to get a good rap simply because of the artstyle change. While the artstyle change is good, it doesn’t automatically make a game groundbreaking.
-Halo 3 ODST
I just found the game boring and not fun in the slightest, playing as an odst is interesting but only gets you so far.
-Halo 5 Guardians
Do I even have to explain? The story is -Yoinking!- terrible with absolutely no redeeming qualities. Even though the gameplay is fun but it doesn’t save this from being the worst campaign… well, second worst
Halo wars 2: Awakening the Nightmare
The game counts it as a separate campaign so i will as well. Halo 5 is bad, but this is the only campaign that straight up pissed me off. I bought halo wars 2 only for the story, i don’t care about the gameplay of this campaign or the multiplayer. So when i saw the E3 trailer i had a hunch that halo was going to get good again, did it deliver? No, it delivered less than halo 5. This campaign is so short and so anticlimactic. I understand halo 5 more than i understand awakening the nightmare. Is the flood destroyed is the flood still out on the loose? I have no f*cking idea because this game doesn’t explain it. I was excited for halo 6, but after this i am legitimately frightened that halo 6 will be another disappointment.