Eternal Sleep

"Eternal Sleep" is an ability wielded by multiple antagonists throughout the Sailor Moon series.

Often used as a tool for punishment by those in higher positions of power, an attack used by minions against the protagonist, or from a main antagonist against a main protagonist.

Sailor Moon
The first reference to an "Eternal Sleep" is the state Queen Beryl put Jedite into when he was defeated by the Sailor Scouts in Ep. #10 Fight to the Finish. Jedite was put into an eternal frozen state, then vanished into infinite darkness.

Queen Beryl later threatened Neflite and Zoycite with the same fate if they continued to fail and question her orders.

Sailor Moon R
The second reference to an "eternal sleep" was in Ep. #62 Prediction of Doom in the episode preview mentioned by Serena (and Luna to Darien towards the end of the episode) for an attack used by the Negamoon Droid, Hypnotica. Sailor Moon's body was invaded by the Droid and she was placed in an "Eternal Sleep" dream world. This caused her to slowly lose all her energy.

Hypnotica was later driven out of Sailor Moon's body when Tuxedo Mask kissed her. The attack was never given an official name by Hypnotica.

Sailor Moon Super S
In Ep. #158 One In The Hand, upon escaping from her mirror, Queen Nehelenia put Sailor Mini Moon into "Eternal Sleep", but Pegasus reawakened her with a kiss to transfer all his remaining power into her body. However this was never mentioned as being an "Eternal sleep", but referred to a "spell" by Nehelenia.