Dark Souls 2 "is an entirely different beast" to the likes of Elden Ring and even the original Dark Souls, according to modder Yui
Prolific FromSoft game multiplayer modder Yui is "close" to being ready to open up alpha testing of their latest seamless co-op mod, this time for Dark Souls 2. Despite it following the the footsteps of their seamless co-op mods for the likes of Elden Ring, Nightreign, and the original Dark Souls, Yui said this DS2 mod's turned out to be a very different kettle of fish and one of their "most complicated and ambitious projects to date".
Showing off their progress in a fresh YouTube video and accompanying blog post, Yui noted that putting these out "is a way for [them] to officially announce that the mod could be done". It's "close" to being ready for alpha testing, albeit with no solid date when that'll begin as of right now.
As for what the process has been like working on the mod over the past year and a bit, the modder admitted that in hindsight, its original announcement in April 2025 was made "a bit prematurely" and that they "probably should have held off until I made more progress". Elsewhere in the post, they wrote that since getting that ball rolling, the DS2 seamless co-op mod has developed into one of their "most complicated and ambitious projects to date".
"Dark Souls 2 is a bit of an outcast in terms of modding and reverse engineering," the modder explained. "Dark Souls 1, 3, Sekiro, Elden Ring, and Nightreign all run on a very similar game engine. If you understand how one game works then you can more or less figure out how things work in the other games too. Dark Souls 2, from what I understand, is a separate branch of the game engine used in Dark Souls 1, with significant modifications. For reverse engineering purposes it's basically a completely different game."
Once its been wrangled sufficiently for the testing to begin, the mod'll offer co-op with up to six players in Dark Souls 2's Scholar of the First Sin edition. Similarly to Yui's Dark Souls 1 seamless co-op mod only working with the remastered version of that game, the DS2 mod won't work with the original Dark Souls 2 due to it being 32-bit, while the Scholar of the First Sin version is 64-bit.
You'll be able to alpha test Dark Souls 2 seamless co-op for free once Yui fires the starting gun, but the ability to report bugs and seek support directly from the modder will initially be limited to their Patreon backers out of the gate.