The Lethal Doggler appeared in 1987 TV series called Hikari Sentai Maskman. The Lethal Doggler was an Earth Imperial Beast who rebelled against the underground empire 300 years prior to the war of the Underground Empire Tube and Hikari Sentai Maskman.
Lethal Doggler was born in a pool deep within the underground filled with evil energies and dark powers. It saw itself as the greatest being and wished to take down all within the underground in order to rule the land on its own. However, the underground kingdom saw the treachery of the creature and laid out a full on assault, attacking it until it could no longer move. Believing Lethal Doggler as dead, the warriors built a pyramid and tomb hidden away from their sight and placed it within, setting up Haniwa Doggler to guard over it and not disturb where it resided.
However even after all of its assaulting, Lethal Doggler was not dead but extremely weakened by the underground's defenses. The creature crawled out of the tomb and used its remaining energy to lay an egg before passing on. The egg hatched into a child, Lethal Doggler II, which possessed the strain and hatred of its parent even from birth. The newborn soon ate its parent's body fully to gather its power and anger, making it instantly grow up and prepare for revenge on the underground. Over the next three-hundred years, Lethal Doggler II would rise and eventually take a new name when he finally accomplished its parent's greatest dream: Earth Emperor Zeba.
Yet due to Lethal Doggler's infamy, Zeba refused to have any knowledge or information regarding his identity or his parent's identity leaked out, forcing the destruction of any means that would reveal it. Yet Thief Knight Kiros, hoping to find information to blackmail Zeba and take Princess Ial's frozen body for his own, raided Lethal Doggler's tomb in belief that he was actually his parent without knowing the full truth. When he saw the tomb had been opened without knowing the truth, he and all other Tube forces started to believe that Zeba was Lethal Doggler. It was further complicated with Kiros discovering Lethal Doggler's blood, which likewise possessed the ancient Doggler's power.
Ultimately it came to a head when Earth Imperial Princess Igam returned to the pond where Lethal Doggler was born in order to find a way to use its power to make herself strong enough to take on the Maskman. Yet when she tries to access the pond's power, she ends up raising the corpse and ghost of Lethal Doggler, who possesses her teacher Godai Doggler in order to fight one last time. The Maskman are forced to destroy the combined power of Lethal Doggler and the Doggler it possessed, destroying the remains of the original Lethal Doggler before being forced to take on its child in their final showdown.