A franchise that has now spanned more than two decades, Halo has seen plenty of first-person shooter campaigns, along with a couple of real-time strategies and twin-stick shooters. The length of first-person shooter campaigns has been relatively consistent since the release of the first Halo title but there is still some variation in length. Regardless, the story in these titles is pretty great, in no small part because of the game's strong characters, excellent worldbuilding, and some truly excellent writing at times.