Pokemon Go raid battles continue to add more excitement to the popular mobile game.

Niantic added an update about the raid battles, including the inclusion of more legendary monsters. Here are seven things you should know about it:

• The popular Silver and Gold monsters Suicune, Raikou and Entei will be added to Pokemon Go in raid battles. They represent the game’s legendary water dog, lightning dog and fire dog respectively.
• Expect these monsters to be rolled out Thursday, Aug. 31.
• Raikou will be available throughout the Americas, Entei throughout Europe and Africa, while Suicune will be in the Asia-Pacific region.
• On Sept. 30, all three of these Pokemon will be moved to a different location and will be available for Trainers to battle with friends until Oct. 31.
• On Oct. 31, they will move again and make their presence in a third location known.
• An EX Raid Battle (formerly known as Exclusive Raid Battle) will begin its field-testing phase at select Gyms before being rolled out around the world. Niantic will examine how people react to the Pokemon Go feature before tweaking and improving it.
• The first EX Raid Passes will be offered soon and those who are invited can try out the new system as early as Sept. 6. Check out more updates on the EX Raid Battles over the weeks ahead.