From Niantic:
Chameleos will start appearing for all hunters at Elder Dragon Interception points starting May 24. A seldom-witnessed elder dragon, Chameleos has been said to have the ability to vanish before one’s very eyes in the rare event that it is sighted. Exhaling a special fog-like breath, it has unique abilities and eccentric movements that are unmatched by any other monster.
Additionally, don’t miss a chance to forge the Mizuha Set armor, featuring a brand-new skill, plus some additional weapons.
A brand-new online event also takes place from May 24–25: Spring Hunt 2025.
In this special event, players can purchase an event ticket to enjoy Elder Dragon Interceptions featuring only Chameleos, no waiting times between Elder Dragon Interceptions and Hunt-a-thons, and bonus Chameleos-themed layered equipment with their purchase. Players will also have the option to choose between two Event Exchange Hubs during the event.
So sharpen your weapons, rally your friends and get ready to take down Chameleos!