Minecraft wiki entry for Raids.dat_format, associated text: : The root tag.
 NextAvailableID: The ID for the next raid to occur.
 Raids: List of compound tags including raid information.
: A raid.
 Active: 1 or 0 (true/false). Whether the raid functionality is active.
 BadOmenLevel: The level of bad omen for the raid. Affects raider enchantments and the extra wave.
 CX: The x position of the center of the raid, where raiders try to move to.
 CY: The y position of the center of the raid, where raiders try to move to.
 CZ: The z position of the center of the raid, where raiders try to move to.
 GroupsSpawned: The number of waves that have spawned in the raid.
 HeroesOfTheVillage: A list of players who have killed raiders in the raid. Each of these players receives the hero of the village effect when the raid ends in a victory status.
: An entry containing the Universally Unique Identifier of a player.
 UUIDLeast: Least significant bits of the Universally Unique Identifier of the player, to be joined with UUIDMost to form the player's unique ID.
 UUIDMost: Most significant bits of the Universally Unique Identifier of the player, to be joined with UUIDLeast to form the player's unique ID.
 Id: The ID of the raid.
 NumGroups: The total number of waves in this raid.
 PreRaidTicks: The timespan, in ticks, until the initial spawning of raiders.
 PostRaidTicks: The timespan, in ticks, after all the waves are cleared.
 Started: 1 or 0 (true/false). True if the raid has ever spawned a wave.
 Status: The status of the raid.
 TicksActive: The timespan, in ticks, the raid has been going on for.
 TotalHealth: The sum of maximum health of all the raiders in the current wave.
 Tick: Internal clock.