I usually use it on supports if I want them to leave the field since it removes their buffs and gives them taunt, so, don't really care if the sleep is permanent or not.
I mean it's Oberon-Vortigern, whaddya expect? He hates humanity and it seems to me that it's a Teeth-Clenched Teamwork on his part. Of course It should be permanent! It's only fitting for him.
I'm stil asking myself how they figure it out to wake the affected servants from eternal sleep lorewise? ...Aside from killing them in their sleep and re-summon them in the process.
The slumber should stay permanent
Should be awaken-able/with less turn count
