Raid Battles are group efforts where Trainers come together to defeat a single strong Pokemon called a Raid Boss. This is also where Legendary and Mythical Pokemon appear during special events! Raid Bosses will hatch from giant eggs atop Raid Towers or EX Raid Gyms. Look at the clock above the eggs to see exactly when the Pokemon will hatch.
The Raid Boss can then be challenged for about an hour after it hatches, depending on the difficulty. Each Raid Boss is rated between one and five stars. Five stars is considered a Legendary Raid Boss, though there are some Pokemon that are tougher than their stars.
A Raid Pass must be used to enter the lobby where nearby Trainers will be waiting to challenge the Raid Boss. A Raid Pass can be earned once per day by spinning the PokeStop attached to the Raid Tower or EX Raid Gym when a Raid Boss is present. Additionally, Premium Battle Passes can be purchased from the in-game Shop for 100 Gold Coins. Up to 20 Trainers can battle a single Raid Boss at one time.
Raid Battles are similar to Gym Battles. The Raid Boss will be controlled by AI, and Trainers control their Pokemon. Pokemon can be switched out during battle, battles can be ended quickly by leaving them, but items cannot be used once the battle begins. Challengers have a set time to defeat the Raid Boss. The time depends on how difficult the boss is.
Tap the Raid Boss to use Fast Attacks and begin charging up the Charged Attack(s). Tap the Charged Attack icon when ready to perform the stronger ability. Fast attacks can’t be used for a few seconds while the Charged Attack is being performed.
Remember, Pokemon have certain types that are stronger or weaker to other types in both attack and defense. Refer to the Type Chart below. Credit to Reddit user Alpha Nation.
Once a Raid Boss has been defeated, Trainers will get a chance to capture the incredibly strong Raid Boss. Raid Bosses can only be captured with special Poke Balls called Premier Balls. These will be awarded to Trainers that participated in the Raid Battle based on their team’s contribution. Play with Trainers on your Friends list to receive extra Premier Balls. Berries can also be used in the encounter with the Raid Boss, but once all Premier Balls are used the Raid Boss will flee.