The mod, according to the description on Nexus Mods (via PCGamesN), gives Witcher characters faster regeneration for their health, Magicka, and stamina. Related: Skyrim: What Happens If You Don't Kill Paarthurnax
These superhuman abilities are carried over in the new mod to Skyrim, where the Witcher race has several enhancements that give it an advantage over the playable races in the base version of the game. In the game's setting, Witchers are mutants that have altered their bodies to be faster and stronger than ordinary humans in order to fight monsters that inhabit the world. Released to near-universal acclaim in 2015, The Witcher 3 featured Geralt of Rivia, one of the titular Witchers, as the game's protagonist. Although the game will be ten years old in November, Skyrim still boasts a prolific modding community that continues to add to the game or reinvent it entirely. References to other franchises are a common theme of Skyrim mods, but the new mod adds elements of The Witcher series that were never available before. Two of the most popular games of the last decade, The Elder Scrolls V: Skyrim and The Witcher 3: Wild Hunt, have crossed over in a new mod that brings in Witchers as a playable Skyrim race.