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

Red Dead Online players in Red Dead Redemption 2 have 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 an Undead Nightmare limited-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 an Undead Nightmare update for Red Dead Online, it wouldn't be the first time we've seen evidence of this in the game. However, to talk about the other Undead Nightmare tease in Red Dead Redemption 2, we'll have to venture into MAJOR SPOILERS for the story.

When players finish Red Dead Redemption 2, Arthur Morgan dies and they take control of John Marston, the protagonist from the original Red Dead Redemption. Players have to get to this point to find the Undead Nightmare easter egg in Red 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 an Undead Nightmare event for Red Dead Redemption 2 as 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 of Red Dead Redemption 2 story 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 2 is out now for PS4 and Xbox One.

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