I heard of a video talking about " They’re coming back… and there’s ALOT more of them this time " And something about diffirent sound’s, im not quite sure, if you heard of it you should know what it;s called. Could someone send me a link to it if you know of it, I have a vague memory of seeing but I forgot what website it was from. I read an article on it, but no video link. If someone post’s a link it would be greatly appreciated 
YH you read a leaked info on halo 4
there are NOO other trailer . only one, the E3 one.
There: http://www.youtube.com/watch?v=gUMb67XzEMs
All you have to do is Google/Youtube; ‘Halo 4 plot’.
Personally i’m torn whether to believe the leak or not, it certainly sounds genuine and despite 343 rejecting it as a fans speculation, they would never say “Oh damn how did you know…”