Whis swiftly karate chops the opponent on the neck, rendering them unconscious. Whis uses this attack make the God of Destruction Beerus stop destroying the nearby planets after eating wasabi and causing him to go on a rampage.
Whis also uses the move to put Vegeta to sleep for a short time during their training session in the movie Dragon Ball Z: Resurrection 'F'. However it is seen Whis has used a bit less effort when performing the attack to Vegeta.
Appearances in games
I Won't Let You! was named in Dragon Ball Z: Battle of Z, where it appears as one of Whis' unique attacks. In Dragon Ball: Xenoverse, it is renamed Strike of Revelation and is one of Whis' Super Skills. Its in-game description reads: "A Strike attack where you close in and seemingly disappear, then strike a hit as soon as you appear behind your opponent." The Future Warrior can also obtain this skill as a reward in Parallel Quest 44: "God of Destruction and His Master".