The originalRed Dead Redemptionfeatured an impressive zombie-themed expansion calledUndead Nightmare, which earned critical acclaim upon its release. A similar expansion forRed Dead Redemption 2has yet to be announced by Rockstar Games, but some Red Dead Online players believe that they may have found the first clues that anUndead Nightmare-style update could be in the cards for the online multiplayer mode.

Red Dead Online players inRed Dead Redemption 2have reported seeing “zombies” in the game’s swamp areas, and other users on Reddit have also said that there are more dead bodies appearing in the swamps than usual. With Halloween right around the corner, this has understandably led to speculation that Rockstar is gearing up for anUndead Nightmarelimited-time event for Red Dead Online, though such an event hasn’t been confirmed at the time of this writing.

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If Rockstar is teasing anUndead Nightmareupdate forRed Dead Online, it wouldn’t be the first time we’ve seen evidence of this in the game. However, to talk about the otherUndead Nightmaretease inRed Dead Redemption 2, we’ll have to venture intoMAJOR SPOILERSfor the story.

When players finishRed Dead Redemption 2, Arthur Morgan dies and they take control of John Marston, the protagonist from the originalRed Dead Redemption. Players have to get to this point to find theUndead Nightmareeaster egg inRed Dead Redemption 2, which lets players see John Marston as a zombie if they go to the well in the abandoned town in Tall Trees, found near the trapper in that area.

If Rockstar does decide to move forward with anUndead Nightmareevent forRed Dead Redemption 2as rumored, it will be interesting to see if it will be exclusive to Red Dead Online, or if it will be available in the story mode as well. We’ve had no word ofRed Dead Redemption 2story DLC, though some fans would no doubt like an excuse to revisit the game’s impressive open world. Since these latest teases are appearing in Red Dead Online, that seems to suggest the rumored update will only be for online multiplayer, but that remains to be seen.

Red Dead Redemption 2is out now for PS4 and Xbox One.

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