It is still possible to spawn a level 1 Purge even though the difficulty is set to level 6. Higher difficulty levels have a higher chance to have more powerful NPCs, spawn more waves and spawn more bosses. Difficulty affects which waves are picked to Purge. In general, the severity of The Purge depends on the area. If you are on a dedicated server or local game, and you are the only one playing, the purge will only pick you. The Purge will occur for whichever eligible player or clan is chosen - whether they are logged in or not again, dependent on the server settings. This will continue until there are no more eligible players or clansor until the Purge Hours are over. Once the first Purge has ended, another eligible player or clan will be chosen to receive a Purge.

During Purge hours, an eligible player or clan will be chosen at random to receive a Purge. Once eligible, a Purge has a chance to occur during Purge Hours which vary depending on Server Configuration. All players within a clan share the same Purge Meter. The Purge Meter fills as players perform various activities in the game, and falls when the player remains logged out and inactive. The Purge involves an army of NPCs or creatures that randomly spawns on the map with the sole purpose of attacking a player-built structure.

It is a semi-random event that occurs based on players' actions throughout the Exiled Lands.