King of Pokélantis

The King of Pokélantis is a villain appearing in the Pokémon: Advanced Generation anime episode, "Battling the Enemy Within" as the main antagonist.

Past
Many centuries ago, possibly millenia, the king ruled over his empire with an iron fist, but he wished to control the entire world and all the Pokémon in it. According to legend, he attempted to capture the Legendary Pokémon Ho-Oh, but this backfired and the legendary bird destroyed his entire kingdom as punishment. However, the king supposedly managed to trap Ho-Oh within a stone orb.

Present
In the present day, Ash and co. literally stumble into an ancient tomb where they meet Brandon, who is ivestigating the ruin. He tells them the story of Pokélantis, but warns them not to venture any further. Ash, however, is too interested in seeing Ho-Oh again and rushes past him. He then finds the statue depicting the king and a throne with the stone orb sitting in it. He picks it up and and calls for Ho-Oh, but instead the ball unleashes a dark force which consumes and possesses Ash, revealing to be the spirit of the King of Pokelantis. As soon as he is released, he attempts to take the others' Pokémon for himself, but Brandon, who introduces himself as King of the Battle Pyramid, challenges the evil spirit to a Pokémon Battle for the fate of all things, which the king of Pokélantis accepts.

In the Pyramid, the king summons Ash's Sceptile to battle Brandon's Regirock. Despite the type disadvantage, Regirock proves formidable, so the king has Sceptile aim for the ceiling to cause debris to fall on his opponent, a dishonorable tactic that Ash would never use. Brandon calls him a coward, causing Ash to break free of the possession, but this was short lived and he was once again taken over. However, Regirock blasts away the rocks entrapping it and prepares to fire a Hyper Beam, but the king orders Sceptile to hide behind the referee, forcing Regirock to disengage the attack. Sceptile then starts aiming for Regirock's legs on the king's order, but Regirock then uses Lock-On and then fires Hyper Beam for a direct hit, defeating Sceptile and winning the match for Brandon.

The king refuses to accept this loss and orders Pikachu to battle, much to others' protest. From within, Ash tells Pikachu to electrify him; Pikachu somehow hears this and does so, finally releasing the evil spirit from Ash's body. Brandon uses the stone orb to trap the king inside again. He then criticizes Ash for being so arrogant, which allowed the king to take control of him in the first place.