The line comes from Dragon Ball Z, the long-running anime adapted from Akira Toriyama's Dragon Ball manga, where Goku is the main hero known for testing his limits in battle. His 'Is that all you got?' taunt became a popular reaction clip online because it sums up his fearless attitude in a few seconds. Fans share it on soundboards, in Discord servers and in short video edits, often alongside the related hey its me goku is that all you got meme phrasing.