The episode stars Marceline and Princess Bubblegum as they go on a journey to the Glass Kingdom to prevent a huge catastrophe from taking place.
Next up is Wizard City, an episode starring Peppermint Butler back at the start as he studies at Wizard School. However, events going down on campus mean he’s the primary suspect.
At the time of writing, there is not a confirmed release date for the episode, or the one which follows – Together Again, starring Finn and Jake.
However, as BMO came out on 25 June and Obsidian was released on November 19, this means fans have speculated Wizard City could be out in April 2021 to match the release schedule so far.