Halo 5: Guardians
Oh the number of things Halo 5: Guardians’ ending did to annoy fans. On top of not focusing all that much on Master Chief, turning Cortana into a de facto bad guy with some lame motivations and rendering the whole Locke-Chief confrontation moot, Halo 5 ended on a cliff-hangar. Really. It ends with all the AI swearing allegiance to Cortana, a Halo installation coming up (that too if you complete the game on Legendary) and nothing else. Totally worth the wait and all those Hunt the Truth podcasts!