Though the Monster has been a constant presence in Season 4 of The Magicians, the audience still knows very little about him. For much of the season, Quentin and co. assumed that the Monster was looking to rebuild the body that was taken from him a millennia ago — but recent information indicates that he's actually out to get revenge for the murder of his sister. These 7 The Magicians theories about the Monster's sister try to get to the bottom of the pantheon of gods that have been shifting in and out of Season 4.
The Monster is not exactly a god. It's a powerful being that was held prisoner in Castle Blackspire, either as punishment for a crime or to keep it from hurting anyone else. The Monster doesn't have a body of its own, which is why it's borrowing Eliot's; because of that, it was easy to assume that its mysterious mission to kill gods was an attempt to rebuild the body it no longer had. However, a journey deep into the Monster's mind revealed that its sister was once killed by gods as a sacrifice. It may be trying to get its sister back, or just get vengeance.
Penny theorized that the Monster's sister was truly the dangerous one, because her supposed crimes led to her death. The Monster was just imprisoned. That may or may not be true, but these theories do their best to figure out this complicated situation.
Reddit user blueskies8484 theorized that the Monster's "sister" was Pandora, a figure from Greek mythology. Pandora famously opened a box that contained all the world's ills, releasing horror and sorrow of every sort into the universe. This user puts forth the idea that the Monster is actually one of the "pure elements" that Pandora released from the box; it wouldn't make them siblings, but it would connect the two. If the Monster feels indebted to Pandora for releasing it, it may look upon her with a sibling's affection and be angered at her death.
A Complex Family Tree
Redditor ChaoticNeutralPrime pointed out that the Monster said he and Bacchus had the same parents. In that case, it stands to reason that one of Bacchus' sisters could also be the Monster's sister. The identity of Bacchus' mother is debatable, but one theory is that his mother is Persephone. She has a daughter named Melinoë, who is a minor goddess or nymph connected to nightmares and magic. Since Persephone and her problem children have already been recurring parts of the show, this could bring it all full circle.
Gods Before Gods
A few fans have theorized that the Monster is Cronus, a Titan who fathered the majority of the Greek pantheon. Cronus had a sister-wife named Rhea. Titans aren't technically gods, but powerful beings who existed before Zeus or Hera ever ascended to Olympus. Cronus and Rhea actually had some conflict, so if that's who the Monster and his sister are, it's unclear why he'd want to revive her. In Greek mythology, Cronus consumed all of his children with Rhea so they couldn't overthrow him — until she hid Zeus from him, which led to the exact situation Cronus had feared. Maybe the Monster only wants to get her back for causing his downfall.
Sister Wives Abound
Redditor CommonSensibility looks to Egyptian mythology for an answer instead of Greek. Osiris was an Egyptian god who was betrayed and dismembered by his brother Set before his sister-slash-wife Isis put him back together. This mirrors the Monster's story in obvious ways, with his body being taken from him in an act of godly betrayal. Osiris seeking to restore Isis would flip the story somewhat, but it would echo back to the references to Egypt scattered throughout the season. A mummy had important advice about the Monster, and Julia found answers about its body in hieroglyphics. Perhaps that's because its origin is Egyptian.
Not So Bad After All
Reddit user Galgos thought perhaps the Monster and his sister were actually good and the gods who punished them were the real villains. They thought the Monster siblings could be Ares and his sister Enyo (both gods of war). They were targeted by Aegnus so he could take Enyo's power before killing her and putting her brother in Castle Blackspire. It's a possibility, though the ice cream man who offered the Monster sprinkles in Episode 1 might have some doubts about how good he is.
Iris was one of the gods killed by the Monster, which Redditor monroeet thought was an important detail. The family trees of gods can make your head spin, but Iris had an uncle and aunt named Phorcys and Ceto who were also married to one another. (The gods were very much into incest.) Phorcys and Ceto were sea gods who apparently had "a host of monstrous children." Monroeet theorized that the Monster and his sister are two of those children, especially because one — a half-snake, half-woman named Echidna — was notably killed on the order of Hera, queen of the gods.
The Answer Was Within You The Whole Time
Redditor sadb****esonly put forth an unusual idea: they believed the Monster's sister might actually be...the Monster. The memory that Penny visited was actually something that happened to the Monster, but because it was so fractured by the event, it believes it happened to its "sister" instead. It would be similar to what Harriet went through in the Mirror World. The Monster may be looking to become whole again after all.
The world of mythology is so vast and varied that the Monster's sister could really be anyone. Her identity may be a twist that fans won't ever see coming.