Minecraft wiki entry for Village_mechanics, associated text: When a player with the 'Bad Omen' debuff enters a village, the Bad Omen effect disappears and a raid occurs. Raids are groups of illagers (pillagers, vindicators, evokers, ravagers, and witches) attacking the village with the intent of killing villagers. They can remove the 'Bad Omen' debuff by drinking milk before entering a village to prevent raids; however, the player can also defend a village from a raid, at which point the player gains the 'Hero of the Village' buff. This causes villagers to give the player steep discounts during trading, as well as bestow various gifts upon the player.‌[Java Edition only]