ThunderCats is an American animated series that first aired in 1985, following a group of cat-like heroes led by Lion-O on the planet Third Earth. The team's battle cry and Lion-O's powerful roar became signature sounds of the show, instantly signalling that the heroes were ready to fight. Decades later, clips of the roar circulate in memes, edits, and soundboards as a shorthand for heroic confidence and over-the-top drama, keeping the 1980s cartoon alive for viewers who grew up with it and for new fans discovering it online.