• English / United States: Siebold
• Japanese / Japan: ズミ
• Japanese (Romanized) / Japan: Zumi
• Japanese (TL) / Japan: Zumi

Siebold is a member of the Kalos region's Elite Four. In addition to being part of the Elite Four, he is also a chef. His main partner Kamex can Mega Evolve into Mega Kamex.

Nurse Joy (Kalos) told Alain that Siebold of the Kalos Region Elite Four had a restaurant nearby, so Alain went to challenge him. When Siebold approached Alain, Alan told him that he wanted to try Zumi's unofficial menu. The two battled in a 1-on-1 Mega Evolution battle and despite the type disadvantage, Alain held his own for most of the battle until he finally lost. Siebold was impressed with Alain as he was powerful enough to corner him even with a type disadvantage. He complemented him on an excellent battle as it had been a while since he "last had fresh meat with a backbone".