People received that first link in an email, I believe. The rest I have no idea how they discovered them. I'm seriously in the dark, but it's suggested that it's maybe a puzzle not unlike what we saw 343 do with the Halo 4 cover. It seems to have come out of nowhere, and has been pretty quiet, which is why I thought I'd ask here. EDIT: Okay, apparently there were 3 stars on that first image which uncovered the first three pics in Link 2. The others I can't say where they were found, at this time. Perhaps the same way.