The Pokémon Company and partner Niantic have announced that Kyogre and Groudon will Join Rayquaza in Raid Battles for its Legendary Week. The week will run from now until March 5, and will also be part of a global challenge. This global challenge will involve special rewards for trainers that manage to defeat Rayquaza more than both Kyogre and Groudon.
If Rayquaza is defeated more than Kyogre and Groudon combined, Pokémon that typically prefer windy weather (for example, Bagon) are more likely to hatch from Eggs from March 5 to March 16. If not, Pokémon that prefer sunny or rainy weather (like Trapinch or Lotad) are more likely to hatch.
Kyogre, Groudon and Rayquaza each have their own strengths and weaknesses, so challenging all three will be a challenge. Bring your strongest Pokémon, and group up with your friends and raid team and head to nearby gyms for a chance to battle and catch them. Remember this is a limited time event and another chance to grab these rare ancient legendary Pokémon.