In an alternate universe during the events of Season 9, two creatures seek out the team of villains gathered by 'Grogar' to find answers to the sudden resurrection and subsequent death of Sombra.
Phantom Tail is Sombra's son and wishes to be reunited with his long lost father. How will he cope when he is lead to believe that his father cannot be revived? Grim Tidings is the half-pony descendant of the goats of Tambelon: an ancient kingdom mostly forgotten by time. How will he take the revelation that the Father of Monsters before him is nothing but an impersonator?

The two will ultimately bond with Tirek, Chrysalis and Cozy Glow in their own ways, helping them along with their tasks, adventures and shenanigans together. However, when the final battle for the fate of Equestria inevitably arrives, will Grim and Phantom be able to save their new friends from their fate of being turned to stone or will they be dragged into imprisonment along with them?