In Skyrim, illusionists can cast spells such as invisibility.
The basic description claims that the spell will only last for 30 seconds.
Apparently "fortify illusion" on armor just reduces magicka costs.
Possibly "fortify illusion" potions have some other effect.
Is there a reliable way to increase invisibility duration from 30 seconds to some much larger number?
Best Answer
The best way to do so is to install a mod.
The Invested Magic mod makes most of those type spells sustained. While active, they remove a portion of your maximum mana cap instead.
In the base game, there is no way to lengthen the duration of an invisibility spell but there are invisibility potions that last longer than 30 seconds.