Fighting Flea was created by Finster which Rita Repulsa shrank and placed on a dog Jason found. Jason's body was then infected with a rash. Kimberly and Jason fought the monster but Jason was affected by the itch. Fighting Flea could shoot needles as well, it was destroyed by the Megazord. He had various cameos after his introduction including a hallucination Lord Zedd's monster Trumpet Top created and Finster recreated him out of the Monstermatic to assist Rito Revolto ambush the Rangers.
Also best monsterous Fighting Flea in classic Episode MMPR during "To Flea or Not to Flee" in made by Zyu2.