Finster made this monster and it caught Kimberly's flu. He was destroyed by the Thunder Megazord. Repellator is actually the Silverhorns from the Season 2 episode The Power Transfer painted green and given a tongue. This was a Power Rangers exclusive villain and the Megazord battle was also Power Rangers exclusive.
Repellator was a green repaint of season 2 monster Silverhorns, with the addition of a red tounge hanging out of the mouth.