• English / United States: Argus Steel
• Japanese / Japan: アルガス·スティール
• Japanese (Romanized) / Japan: Algus Steel
• Japanese (TL) / Japan: Algus Steel

Argus Steel is a famous Pokémon bandit that was attempting to catch Diancie in order for it to make diamonds for him. His daughter is Millis Steel. He owned a large flying ship that could partially cloak but it was destroyed by Yveltal during a battle and it crashed into a lake. He loves chocolates and had ordered some all the way from the Houen region. He is big in stature and his daughter worries about his health by eating too many chocolate.

In the movie credits, he and his daughter are seen running a chocolate shop.