As for what the hell the episode 50 Broadcast ED is, the final episodes of mist Sentai series, when first broadcast, had the credits scroll over the end of the episode, and had the new show announcement in place of the standard ED, which was then followed by the preview for the first episode of the next Sentai series. However, it wasn't until Liveman that Toei kept this format for the archival masters. This is only on the set at all because Toei had an old tape master sitting around. (The New Show Announcement is not included in these volumes, but it was included in Maskman volume 1)