If you want to play Elden Ring Nightreign in a duo, the Seamless Co-op mod is already out, dead simple to use, and it won't mess up your vanilla save
FromSoftware is apparently reserving the right to add an official two-player mode to Elden Ring Nightreign—right now you can only play solo or in a trio. But Yui, the modder behind the Seamless Co-op series of Souls multiplayer hacks, has already done it again with Elden Ring Nightreign a mere day after launch.
PCG senior editor Wes Fenlon and I hopped in for a round, and it works exactly like you hope it would—it's even slightly more buttoned up than the already-great original Seamless Co-op, won't mess up your game by drawing Easy Anticheat's Eye of Sauron, and even opens up Nightreign for further modding.
To install Seamless Co-op, you just have to whack the files from Nexus Mods into your Elden Ring Nightreign/Game folder. It runs from its own .exe, does not interact with FromSoft's official servers, and creates separate save files from the original game, keeping EAC out of things.
That does lead to a lone hitch for you to consider, though: Any progress you've made so far won't carry into Seamless Co-op, and vice-versa. Wes and I had to chop through the tutorial Margit encounter again before queueing up. This seems to be the cost of doing business, but worth keeping in mind.
Otherwise, though, it runs exactly like the official game—you can even invite friends to group up through Steam still. It also worked perfectly in our run: No hitches, glitches, or connection issues to speak of. It just works. If you don't mind the split progression, have a special Elden someone in mind to play the game with, and can't stand a third wheel tagging along, this is the mod for you.
I thought the first Nightlord felt easier than I remembered, but that was just 30 hours of experience talking: Yui told us that she hadn't touched difficulty balancing in any way for two-player. That may be the lone exculpatory factor in a modder whipping up a two-player mode so quickly when FromSoftware did not.
In FromSoft's defense: It's still clearly finding the balance for Nightreign's solo mode, while Wes and I saw the potential for some lopsided, frustrating gameplay when one player goes down and the other has to revive them in a duo—you no longer have the sturdy tripod of a third player taking aggro. All the same, Yui's work remains, as ever, incredibly impressive, and it'll be interesting to see how Seamless Nightreign develops, especially if FromSoft ever comes up with its own two-player solution.
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