Before we dive in, a quick clarification for your viewing journey. The TV series adaptation officially ran for two seasons (originally on MTV, then Spike). There is no "Season 12." However, the author of the books, Terry Brooks, has written over 30 novels in the series. If you are looking for the equivalent of "12 seasons" of content, the books are where the journey continues!
There is no Season 12. Stop searching for it. Instead, focus on securing the Dual Audio versions of Seasons 1 and 2 . the shannara chronicles season 12 dual audio