7. Halo 3 - The Flood
Let's face it. The Flood are a massive pain the ass. Whereas in Halo: Combat Evolved they were a surprising and scary element, by the time they appear in Halo 3 they have become a clichéd, tiresome enemy whose only real attack was to swarm the player. This leads to many moments of Master Chief, humanity's last hope, to bounce around like a like a kid on crack whilst firing randomly and hoping the shots hit. It was becoming clear that the fans were tiring of The Flood by the time Halo 2 hit the shelves, which makes their inclusion in Halo 3 such a mystery. Yet Bungie not only included them in the game, they decided to devote an entire level to them. The level in question goes by the name "Cortana" and it appears towards the very end of the game which, somehow, makes it more frustrating. Cortana is under the control of the Gravemind and it is up to Master Chief to find her and cleanse High Charity of all Flood that can be found. And there are a lot of them. It all starts off pretty straightforward but soon devolves into exactly the kind of mindless blasting that the original Halo was praised for avoiding. The frustration you feel is only heightened by the level design which leads to more than one instance of running around like a child lost at the supermarket due to the fact that almost every area looks exactly the same. A surprisingly shoddy piece of level and enemy design from one of the pioneers of modern gaming and a real stain on what is, otherwise, a fantastic achievement. Oh, and if you're reading this thinking "it wasn't that bad", try doing it solo on Legendary and let me know how many controllers you burn through (or just burn).