One of the newest concepts that has since been added to Pokemon GO is that of raid battles. Raid Battles take place randomly at Pokemon Gyms, were up to twenty different players can attempt to defeat a Raid Boss. Raid Bosses are Pokemon that have extremely high Combat Power Levels, ranging from anywhere between 1,000 CP to 50,000+ CP depending on the Raid Battle Level. Raid Battles have five different difficulty levels; the higher the Raid Battle Level, the more rare and strong the Raid Bosses will be. After defeating a Raid Battles, player will not only receive loads of rewards, but they will also have the chance of catching the Raid Boss they just defeated.
Players will know a Raid Battle is coming to a pokemon gym when a giant egg appears on the top of the gym. Once one of these giant eggs appears atop of a Pokemon Gym, a countdown clock will begin that will show exactly when the Raid Battle will begin. Pink Eggs tell of a Level 1 or Level 2 Raid Battle, one with a very common Pokemon as the Raid Boss. Yellow Eggs tell of a Level 3 or Level 4 Raid Battle, one usually with an extremely rare Pokemon as its Raid Boss. Silver Eggs tell of a level 5 Raid Battle, one that guarantees a legendary or Mythical Pokemon as its Raid Boss. Once these giant eggs hatch, players will have a set limit of time to defeat said raid battles.
In order to participate in a Raid Battle, a player must have a Raid Pass. Players can obtain one free Raid Pass per day from any given PokeStop; however, they can only hold one freebie Raid Pass at any given time. Should a player desire to have more, they can purchase more from the game's Shop in exchange for some PokeCoins. Any good Pokemon GO player should be able to defeat Level 1 and Level 2 Raid Battles on their own; Level 3, Level 4 and Level 5 Raid Battles usually require a lot more participants in order to be defeated.