Legendary Pokémon Kyogre and Groudon are returning to Raid Battles alongside currently featured Legendary Pokémon Rayquaza for Legendary Week from Feb. 23 until March 5.

Niantic, the developer and publisher of "Pokémon GO," announced the news in an update in the game's official website. According to Niantic, players will have to head to the nearest Gyms for a chance to battle and catch the Generation 3 Legendary Pokémon. Moreover, Niantic will count each defeat to decide the winner of the global challenge — the most number of defeat will determine the Pokémon that will be hatched from Eggs from March 5 to March 16. If more Rayquaza is defeated than Kyogre and Groudon combined, Pokémon that typically prefer windy weather (Bagon, for example) are more likely to hatch from Eggs. However, if more Kyogre and Groudon are defeated than Rayquaza, Pokémon that prefer sunny or rainy weather (like Trapinch or Lotad) are more likely to hatch.

Forbes thinks defeating Rayquaza is a better option for players. This is because Pokémon that prefer windy weather such as the dragon, flying and psychic types are more difficult to find as compared with Pokémon that prefer sunny or rainy weather such as the fire, grass and ground types for sunny weather as well as the water and electric bug types for rainy weather. 

Eurogamer also highlighted Feb. 24 as a date that "Pokémon GO" players who are interested in participating in the Legendary Week should have kept in mind. The second day of the event, Feb. 24, saw the debut of new Special Boxes on sale in the in-game shop. They contain Premium Raid Passes that will help players participate in Legendary encounters more than once a day.