The episode stars Marceline and Princess Bubblegum, who must go on a journey to the Glass Kingdom and delve into their pasts to prevent a huge catastrophe from taking place.
The major characters in this episode are Princess Bubblegum, Marceline, Glassboy, See-Thru Princess, Larvo, Glassassins, Elise, Sandy, Limeston and Sir Soda.
Other characters you will see include The Morrow, Choose Goose, Simon Petrikov, Ancient Glass Princess, Bronwyn, Finn, Smudge, Cherry Cream Soda and Dirt Beer Guy.
The episode takes place a few years into Princess Bubblegum and Marceline, so fans have concluded that the timeline is not too long after the events of the Adventure Time finale – Come Along With Me.
To stream the full episode of Obsidian, fans can check out a seven day free trial of HBO Max before paying $15 a month for access to the platform.