The clip comes from Shadowverse, the Japanese digital card game first released in 2016, where Cassim is a playable character card voiced in Japanese. His phrase kimetakara, written as 決めたから, is tied to his card effect and became easy for players to isolate because it is short and self contained. Japanese fans often shorten the game name to Shadoba, and short voice captures like this circulate in fan soundboards, streams and edit communities where a single character line can signal a decision without needing the full match context around it.