Removing Legendary Skill Ranks in Skyrim?

Solution 1:

I'm not aware of any way to do this in the console, but SKSE does expose a scripting API for adding and removing legendary levels, if you're willing to get your hands dirty writing your own mod. You could do something like the following in a Papyrus script:

ActorValueInfo.GetActorValueInfo("Marksman").SetSkillLegendaryLevel(0)

(This cannot be typed at the console; it has to be compiled into a Papyrus script and then executed by the game's scripting engine. Also, it requires a reasonably recent version of SKSE - if for some strange reason you must use an older version, use the deprecated Game.SetSkillLegendaryLevel() instead.)