Veofum was a selfish, ruthless, and greedy king who wanted the power of Xerneas so he could bring prosperity to his land. However, instead of flourishing it, the plant life in his kingdom wilted and the Pokémon began dying. Angered at this, he order his men to burn Xerneas. Jan arrived and tried to stop Veofum from burning Xerneas, but he refused. Veofum ordered his men to get rid of Jan, when suddenly, the Legendary Pokémon Zygarde appeared. Zygarde used Land's Wrath to destroy the kingdom, which led to the demise of Veofum and his henchmen.
(Source: Bulbapedia)
