This is a list of Happy Tree Friends episodes. So far, there are total of 5 seasons that have been aired (4 on the internet and 1 on TV). In 1999, the crew began the series with two pilot episodes. The very first pilot was named Banjo Frenzy, which featured a blue dinosaur, a sky-blue squirrel, a yellow rabbit and a purple beaver. The second pilot was named Spin Fun Knowin' Ya! and featured later versions of the dinosaur, the rabbit, the squirrel and the beaver and, from that on, the crew began introducing new characters to the show. It quickly became an internet phenomenon featuring millions of visits per episode. The TV series first aired in 2006.