The latestMarvel Studiosseries to premiere on Disney Plus has already begun to spur fan theories. With only two episodes thus far, Oscar Isaac’s dual performance inMoon Knightalready has fans captivated, as they eagerly await what’s next. One fan has begun to imagine what could be next forMoon Knight, and has revitalized a popular theory that fans ofWandaVisionwill recognize.

WandaVisionwasMarvel Studios' first television series as part of the MCU. It followed Wanda Maximoff shortly after the events ofAvengers: Endgame,which left her seeking comfort in what would soon become a massive problem.The nine-episode Marvel seriesgained a massive following and earned a whopping 23 Emmy nominations. Within the complex world ofWandaVisionand The Hex Wanda has created, a number of theories began to take form, including the arrival of potential characters.

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BeforeWandaVisionrevealed that it was Agatha all along, fans had begun to theorize that a sinister Marvel villain was going to be introduced in the series. One Marvel fan has taken theWandaVisiontheory of Mephisto and plugged it into the context ofMoon Knight. The photoshopped fan image byStephen Kleintakes theMoon Knightposter of Steven’s goldfish and transforms the innocent pet into a merevessel of Mephisto’s evil motives. The goldfish’s once bright orange hue is now a deep shade of red and its eyes glow a blinding shimmer of white. At the base of the container Steven returned to the pet store with is a thread of red magic that suggests Mephisto is up to no good.

Moon Knight’s debut episode, “The Goldfish Problem,” placed a great level of emphasis on Steven’s pet goldfish. At the start of the episode, Steven stresses that the goldfish only has one fin. Later in the episode, after having several strange experiences, Steven notices that the goldfish now has two working fins. Steven tries to take the fish back to the pet store to gain some insight rather than chalking it up as some form of magic, but it only results in more confusion. The fan image suggests that the sudden change in Steven’s pet isn’t because of Marc Spector’s presence, but because of Mephisto.

Mephisto has a long history of squaring off with some of Marvel’s biggest heroes, including Scarlet Witch. Despite a number of hints that fans identified throughoutWandaVision(including a cicada that many were certain was Mephisto), Mephisto never arrived. Rumors surroundingcameos inDoctor Strange in the Multiverse of Madnesscould also eventually point to the arrival of Mephisto and countless other fan theories. As a character who only gives to receive something greater, Mephisto certainly fits in with the themeMoon Knightis currently operating with, but his presence in the series is far from likely.

Mephisto’s ability to transform into any object very well means he could behiding in any Marvel project, secretly guiding the catastrophic events that any hero might face. WhileMoon Knightdoes not seem to be geared toward any massive unveiling of a secret villain, it’s fun to continue to play with the famousWandaVisiontheory, and wonder if and when Mephisto will ever appear in the MCU.