hypnosis
Spore!!! the move is spore
the move hypnosis
use sing :P
spore
sing that's it
Sing Sleep Powder Rest Yawn Leaf Whistle
grass whistle
There isn't one.
sleeping powder
The move Dark Void puts its opponents to sleep however in a double battle it'll put both of its opponents to sleep.
Spore is a move that puts Pokemon to sleep and ends with the letter E.
There are many moves for that, such as Hypnosis, and Sleep Power.