Tachigami wrote...
No, it's not the Flood, but 343 is being extremely hush-hush about what your new enemy is.
the new enemy is called the "Prometheans" Here is some info from halo wikia on them. However in the bit they show you in campaign, you do fight the occassional covenant.
The Prometheans were the highest and most respected group of Warrior-Servants in the Forerunner ecumene. The Didact, the Confirmer, the Grammarian and the Strategos were Prometheans.
Physically, Prometheans were the highest form a Warrior-Servant could mutate to, standing around two times the height of a Manipular and weighing about four or five times a Manipular's mass. They were heavily muscled, their hands capable of easily crushing a human. Their mental capabilities were also very sophisticated; it was common for a Promethean to share information and sensory input with the warriors under their command. Like Warrior-Servants in general, the Prometheans were capable of controlling a million remote-controlled craft, such as weapon-ships, simultaneously.
The Prometheans were responsible for creating "Warrior Keeps" known as Cryptums, where an exiled warrior could live in suspended animation for thousands of years. Prometheans were also known to employ various kinds of war machines in battle, including Knights, Watchers, and Crawlers.
UPDATE! Seems the prometheans we are going to fight are just autonomous Forerunner defensive constructs. Not the actually real deal. but I dunno if we will be having to fight the actual prometheans themselves.