Arguably the most painful stretch for fans. Season 4 is massive (20 episodes). The MKV file for this season is often the largest in the collection due to the complex VFX of the Paris siege and the visceral, slow-motion death of Ragnar in Episode 15, "All His Angels." The snake pit scene is a codec stress test—the subtle hissing in the surround channels is preserved flawlessly in a good MKV rip.
(for a media server like Plex, Jellyfin, or Kodi): Vikings S01 - 06.mkv