Without USSEP, most serious mod lists consider Skyrim "broken." With it, the game runs as close to intended as possible. To understand why "USSEP 1.5.97" is a specific search, you need to understand the Anniversary Edition disaster of November 11, 2021 .
Bethesda released the Anniversary Edition, which updated the free Skyrim Special Edition from version to version 1.6.x . This update broke thousands of mods—specifically those using SKSE (Skyrim Script Extender) DLL plugins. Mods like Engine Fixes , True Directional Movement , and Nemesis required weeks or months to update. skyrim ussep 1.5.97
In response, a massive contingent of players their game back to 1.5.97 using tools like the Unofficial Skyrim Special Edition Downgrade Patcher . Why? Because 1.5.97 was stable, every mod worked perfectly, and there was no benefit to 1.6.x unless you wanted the mediocre Creation Club content. Without USSEP, most serious mod lists consider Skyrim