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Overall, the establishment of a PvP window allows settlement leaders some control over when they are likely to be attacked, so they don't have to worry about having people online at 3 AM on the off chance that their enemies might come calling. Instead, most settlements will set their PvP window to be open when the highest number of their members is online. The PvP window also concentrates PvP activity into smaller bursts of activity—keeping PvP active and interesting requires a critical mass of players online, and if all the players are spread out over the entire 24-hour cycle, it is less likely for PvP battles of significant size to develop.