However, CVG reports that, as promised, The Flood will not appear in the campaign but will be included as part of a multiplayer mode, "Flood," which is a variation of Halo's long-running "Infection" game type.
However, when a new image of revamped Flood infectees appeared online, gamers began to wonder if the enemies might actually make a return after all. 343 Industries listened and promised that, while Halo 4 follows the events of the prior trilogy, the new installment wouldn't actually include The Flood as campaign enemy types. While some players enjoyed the parasites' final campaign appearance in Halo 3, many gamers were ready to see the franchise move on - or, at the very least, significantly mix-up The Flood format. However, after three Master Chief-centric game appearances by the creatures (not to mention as a Halo Wars faction), The Flood began to look more like a franchise hold-over - without any significant evolution or story function. Back in 2001, when Halo: Combat Evolved was first introduced, the creatures served a specific gameplay function - to provide stronger, more resilient, and diversified variations of established enemy types. The first three Halo titles relied heavily on the zombie-like gameplay and narrative elements provided by The Flood, parasitic organisms that could infect, and subsequently control, humans and other sentient life forms. New screenshots reveal that as 343 introduces fresh elements, such as a mech vehicle (the Mantis), they're also reaching back into the Halo canon, reintroducing The Flood parasites for multiplayer, in order to provide as many engaging gameplay possibilities as possible. While 343 is very clear about where they intend to take Halo in the coming years, possibly through Halo 7, 8, and 9, they're also not afraid to revisit some of Bungie's best inventions. The developer has been very careful about honoring Bungie's creation, as well as the larger canon mythology, but (as with any long-running series) 343 also needed freedom to move the franchise in a fresh direction. When Halo 4 was first officially revealed at E3 2011, the epic announcement trailer teased an entirely new storyline for Master Chief - allowing the team at 343 Industries to drastically change-up existing plot and gameplay elements.