A tag used by scene groups to indicate the release might not meet certain standard "scene rules" or is a secondary release for a specific reason.
The video codec used to compress the file. XviD was a standard for Standard Definition (SD) video for many years. Watch Helix S02E10 INTERNAL HDTV XviD-AFG-[GTtvSD]
The show title ( Helix ), Season 2, Episode 10 (titled "Mother"). A tag used by scene groups to indicate