At the end of the week, eggs hatched between March 5th and March 16th will be based on the associated weather type of the legendary Pokemon that was defeated the most.
For example, If Rayquaza is beat down the most, Bagon is more likely to hatch. Trapinch for Groudon and Lotad for Kyogre are the other examples Niantic used in their announcement.
There will also be new item boxes available. You can check out all of the boxes that have been available on our Legacy Special Box List. See below for the official announcement.
Windy 10KM Eggs - Rayquaza
Sunny 10KM Eggs - Groudon
Rainy 10KM Eggs - Kyogre
Now is the time to test your strength! Legendary Pokémon Kyogre and Groudon return to Raid Battles alongside Rayquaza for a limited time. Now is an excellent chance to finally catch all three ancient Legendary Pokémon originally discovered in the Hoenn region!
Kyogre, Groudon, and Rayquaza each have their own strengths and weaknesses, so challenging all three will take skill! Power up your strongest Pokémon, grab your friends, and head to nearby Gyms for a chance to battle and catch them from February 23 until March 5.
We’re in for some legendary battles, and the overall result will be exciting! 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.
These battles will be tough, so we have new special boxes debuting on February 24, containing Raid Passes to help you prepare. Visit the in-game store to find out more.
Did you know Pokémon is celebrating a ‘legendary’ year in 2018? You can learn about more about these and other Legendary Pokémon at Pokemon.com/Legendary.
Don’t miss this opportunity to add these Legendary Pokémon to your team. Stay safe, and happy exploring!
—The Pokémon GO team