Regice was made available around the world in Pokémon GO Raid Battles until today, July 19, at 20:00 UTC. The Legendary Ice-type Pokémon has officially been replaced by Registeel until August 16, when it will be replaced by Regirock. These Legendary Pokémon can be caught only with the Premier Balls you earn from defeating it, so you’ll need your Pokémon to perform well in battle to maximize your chances. You can participate in Raid Battles even if you’re not high-level or if your Pokémon aren’t the strongest, but you’ll have an easier time if you prepare.
In addition, new Raid Bosses have been added to the game. Alolan Raichu and Alolan Marowak are now appearing for the first time. Alolan Exeggutor is also available as a Raid Boss for a limited time. Charmander, Makuhita and Meditite are level 1 Raid Bosses; Alolan Exeggutor, Magmar and Kirlia are level 2; Alolan Raichu, Machamp, Flareon, Porygon and Donphan are level 3; Alolan Marowak, Houndoom, Tyranitar and Absol are level 4; Registeel and the soon-to-be-added Zapdos are level 5.