^Those two options together just seem really dirty for some reason. Anyway...

Maybe it was something they were playing with (like Bungie with Forge World) and realized after release that they could publish it as a playable map? If I remember correctly, Forge World was originally separated and Chris Carney and Steve Cotton were kind of the two that spearheaded the idea of uniting those maps as one. I'd imagine something similar here with Vic Deleon and Kynan Pearson tinkering with the beginning of their Forge Islands and realizing, "hey, we can do this" and then releasing it to the masses. Their revelation just seemed to come after release as opposed to before.

Once again probably another decision tied to the rush of assembling the studio and releasing a Halo game without a solid hierarchy to begin with. Maybe we'll get the 'focused' maps and a Forge Universe in Halo 5 to begin with?

- MacGyver10