The Haou Shoukou Ken (覇王翔吼拳), also spelt as Haoh Shoko Ken, is a super attack appeared in SNK's Art of Fighting and The King of Fighters. This powerful wide energy shot was invented by Takuma Sakazaki (though he names it Haou Shikou Ken), the founder of Kyokugen-ryuu Karate.
Note that a futaba channel meme called "(武器を持った奴が相手なら) 覇王翔吼拳を使わざるを得ない", lit. "I can't help but use Haou Shoukou Ken (to battle against armed enemies)" is not directly related to this tag. If you find images related to this meme, use ryuuko no ken, parody, meme and motor vehicle (or motorcycle, if necessary) tags. (e.g. post #995128) See also KnowYourMeme.