Chaos wasn't even on that list. Therefore, whatever shells over at that site trying to make up fancy lists if only to connect to a varied and generally estranged species (Sci-Fi enthusiasts or "nerds") can go eat dicks. I mean, seriously, Flood? Yes, I'm going to be afraid of a particularly persistent mass of oatmeal that has a bad habit of making you resemble shit. Now, if you want so real twisted fucks, take a look at the Combine, evil foreign dictators that will bombard a town with zombie-creating headcrabs instead of conventional explosives just to wipe them out, or the Tyranids; swallow your world whole, spit chattering little hellspawn out by the billions. And, no offense, I love the Daleks, but they -occasionally- have problems going up stairs and closed doors. And any persistent Stargate SG-1 watcher can understand how persistent (if sometimes clownish) a thread the Goa'uld can be, but they're understandably like one giant fighting family of royal in-breeds, with the majority of the population of the known galaxy under a hopeless slavery up until the eighth season, and were personified as vengeful gods; not unfounded, because I know when I saw a pissed off Ba'al or Apophis or Anubis, I shat bricks. That's go to earn them something.
Call me a fanboy, but my love of sci-fi reaches far and wide, and I just have to say this list was shit, and it could take paragraphs of justification to satisfy me regarding the "badness" of a particular species.
Oh, and COLOSSI? ffffffffffffffffffffffffffffffffffffff