Red Dead Redemption 2's main story is very long. Here's how long it is, though the answer is a little bit complicated.
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How long is red dead redemption 2 ? : r/reddeadredemption
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Getting the Legend of the East outfit before the Epilogue was less painful than I thought it would be! Guide to the challenges included in the comments. : r/reddeadredemption
Red Dead Redemption 2 details revealed: 60 hours long, 500,000 lines of dialogue, 300,000 animations