Minecraft wiki entry for Raid, associated text: The number of waves depends on difficulty: There are 3 waves in Easy difficulty, 5 in Normal, and 7 in Hard. In Hard, there is a chance of 1 additional pillager and/or vindicator spawning. If the player's Bad Omen level is II or higher, one additional wave spawns (e.g. 4 in Easy, 6 in Normal, and 8 in Hard) with the same strength as the final wave. Raiders have an increased chance of spawning with enchanted items with higher bad omen levels, a 10% chance starting at Bad Omen II and up to a 75% chance at Bad Omen V.