Shamus (Japanese: スワマSuwama) was the former owner of Ash's Tepig who made his official appearance in BW079. He first appeared in the Astilbe Town Battle Club pass Twist Mountain battling a trainer with a Mienshao and Watchog in a double battle, easily winning with his impressive combos with his Fire Warrior team: Emboar and Heatmor. After winning, he proceeded to pick on the loser to let Shamus see his Pokemons from anyone with potential, infuriating Ash and company. They confronted him to stop all this, but Shamus simply forgets about getting his hands on his Pokemons and brushed off the conversation since Don George came by, then walks off.
Later on, Tepig ran up to him while he was eating, seemingly knowing him. It was then that he revealed that he abandoned Tepig in the Accumula Town Battle Club after it lost, believing that Tepig was weak. To prove his point, he challenged Ash to a double battle against Ash's Snivy and Tepig.
The next day, shortly after beginning the battle, he reveals to Tepig that he was feigning caring about Tepig and could care less about it and then looks for another Tepig that has less talent than it was in order to replace him. All he could care about is "power". Shamus held the upper hand in the battle as Heatmor erased the effects of Attract on Emboar with Fury Swipes and managed to knock out Snivy with a combo move of Fire Spin and Flare Blitz. Tepig held on just long enough to regain its confidence and evolve into Pignite. Using its powerful new Fire Pledge and Flame Charge as a combo, Emboar and Heatmor were defeated, surprising Shamus. Afterwards, he offered to take Pignite back as a result for losing to Ash, commenting on its power to use to make him his New Fire Warrior member. Pignite simply answered him with a Flamethrower to his head with a word meaning no because he liked Ash better than him. In which it was and outrage to him and ran away hoping that he'll remember for this.
Shamus calls himself the "Fire Warrior" due to his choice of using Fire-type Pokémon in battle.
Shamus does has the evil looks in his eyes just like Lelouch from Code Geass, who has the same Seiyuu who voice Shamus.
Shamus has a bad reputation when he goes out on the run getting his hands on Pokemons from trainers all over Unova with potential when he wins in a Pokemon Battle.
Shamus is always up to no good when he abandons Tepig at the Accumula Town Battle Club. In which it makes him the villain who wants power more than anything. In which Shamus knows that power is everything to him including his Fire Warrior team Emboar and Heatmor.