Halo 3: ODST launched in 2009, developed by Bungie as a spinoff game in the iconic Halo franchise. The game is set during Halo 2, telling the story of a group of Orbital Drop Shock Troopers (ODSTs) and their fight against the alien Covenant in the city of New Mombasa as their mission suddenly changes course.

It looks like Helldivers 2 might be getting a Halo crossover if a new trailer is to be believed, and there's a very specific game in Arrowhead's sights.