Diabolico is the original antagonist of Lightspeed; a general of Queen Bansheera. He's a demon equipped with Star Power. His first documented appearance was when he offered Capt. Mitchell to save Ryan from death (while they were about to fall off a cliff) and took him into his 'care'. He displays a very serious dispostion and serves as a figurehead to all the demons in Mariner Bay. Queen Bansheera keeps in close contact with him. After he set his three greatest demons after the rangers, it became apparent to Bansheera that he wasn't competent to lead the demons. She repeatedly threatened to destroy him and give the Star Power to Impus. Thus, he shows a deep disgust for the little 'prince', dreaming often of destroying him. Bansheera didn't have the chance, however, as when Diabolico finally faced the rangers himself, he was suprised by a newly recovered Titanium Ranger combining his Max Solarzord with the rangers' Lightspeed Megazord to form the Lightspeed Solarzord which not only absorbed the energy he used to try and fry the rangers, but also rained heavy firepower on him, destroying him, and releasing the Star Power. Bansheera took this opportunity to give the now-free power to her child and enveloped Impus in a coccon suspended over the city. Diabolico eventually got revived and was able to face Impus once again in rthe form of Impus, now known as Prince Olympius, was revived in advanced form along with Olympius and was destroyed by Lifeforce Megazord. Fiercely loyal, he tries assists his friends Vypra and Loki and turns on Queen Bansheera when she kills Vypra. After he saw her sword in Bansheera's tranformation chamber and he was forced to destroy Loki against his will. In The Fate of Lightspeed, Diabolico assists the Rangers in spiritual form in sealing Bansheera up in the Shadow World.
Diabolico is armed with skull-headed staff with axe-like blades in normal form and a sword in super-demon form.