Niantic has confirmed that the next Mythical Pokémon to be added to Pokémon GO is none other than the DNA Pokémon, Deoxys, which will soon be available for the first time via EX Raid Battles. This Psychic-type Mythical Pokémon will be available to challenge in its Normal Forme beginning with the next cycle of EX Raid invitations. You can become eligible to receive an EX Raid Pass when you win a Raid Battle at a qualifying Gym. And from now on, you’ll be able to see which Gyms can host an EX Raid through a tag when you look at the Gym details. EX Raid Passes for Deoxys encounters are now being distributed to players. They give you the date and time when you’ll be able to challenge the Mythical Pokémon, which happens to be on October 1 or October 2 depending on your location.
Battling Deoxys will be a “difficult challenge” that requires Trainers to take advantage of every opportunity. From now on, when you receive an EX Raid Pass, you will be able to invite one friend to go with you. Keep in mind that invites can only be sent to an Ultra Friend or Best Friend, so don’t forget to battle with friends, send Gifts and trade Pokémon to build up your Friendship level. Earlier today, a number of players encountered a glitch that activated EX Raid Passes for standard Raids. Niantic is aware of the issue and has confirmed that it is unable to restore cancelled EX Raid Passes. However, EX Raids will still happen as scheduled. If your friends have passes that weren’t cancelled, they are still able to participate in the EX Raid.
Source: Niantic Support @NianticHelp