Shadowcloak of Nocturnal is a skill awarded to the Dragonborn by Nocturnal in the final Thieves Guild quest Darkness Returns. Stepping on the Crescent Moon platform confers this skill. The skill is listed under Powers.
Once a day, you can automatically become invisible for 120 seconds while sneaking. As with the conventional invisibility spell, you will become visible again when interacting, but unlike said spell, you can freely become invisible again by exiting and re-entering sneak mode for the duration.
- The Shadowcloak only appears to turn the Dragonborn invisible when they go from standing to sneaking. If they are already sneaking when they activate the ability, they will not appear invisible until they stand up and engage sneak again. This applies any time the invisibility is broken, such as interacting with objects, people or doors. Whether or not this actually affects visibility to enemies remains to be seen.
- Once the power is used, shifting into and out of sneak activates and deactivates the invisibility. Even after the two minutes has passed, the Dragonborn will still be able to activate and deactivate the power by standing and sneaking. The ability doesn't truly expire until the they interact with something whilst sneaking that breaks the invisibility spell.