Rat King
Medium monstrosity, lawful evil Armor Class: 14 (natural armor) Hit Points: 225 (30d8 + 90) Speed: 30 ft., burrow 20 ft.
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 16 (+3) | 14 (+2) | 16 (+3) | 14 (+2) | 14 (+2) | 14 (+2) |
Skills: Perception +8, Stealth +8, Survival +8 Senses: darkvision 60 ft., passive Perception 18 Languages: Common, Undercommon Challenge: 12 (8,400 XP)
Traits
Keen Smell. The rat king has advantage on Wisdom (Perception) checks that rely on smell.
Nimble Escape. The rat king can take the Disengage or Hide action as a bonus action on each of its turns.
Pack Tactics. The rat king has advantage on an attack roll against a creature if at least one of the rat king's allies is within 5 feet of the creature and the ally isn't incapacitated.
Rat Swarm Coordination. The rat king can command up to 10 swarms of rats within 120 feet to move up to their full speed and attack as a single action. These swarms act on the rat king's initiative. Each swarm has its own set of actions and is treated as a separate creature.
Actions
Multiattack. The rat king makes six attacks: four with its claws, one with its bite, and one with its tail.
Claws. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 4) slashing damage.
Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 4) piercing damage. If the target is a Medium or smaller creature, it must succeed on a DC 17 Strength saving throw or be grappled (escape DC 17). Until this grapple ends, the target is restrained, and the rat king can't bite another target.
Tail Whip. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 10 (1d12 + 4) bludgeoning damage, and the target must succeed on a DC 16 Strength saving throw or be knocked prone.
Plague Breath (Recharge 5-6). The rat king exhales a cloud of infected breath in a 30-foot cone. Each creature in that area must succeed on a DC 14 Constitution saving throw, taking 21 (6d6) poison damage on a failed save, or half as much damage on a successful one. The creature also gains one level of exhaustion on a failed save. If a creature affected by this breath weapon already has one or more levels of exhaustion, this effect only causes the exhaustion to worsen if the failed saving throw result is worse than the previous one.
Swarm Defenders. The rat king can command swarms of rats within 60 feet to provide cover and defense for it. While this ability is active, each swarm of rats gives the rat king a +1 bonus to its AC, up to a maximum bonus of +5. When the rat king moves more than 10 feet away from any of its swarms, it loses the bonus provided by that swarm until it moves back within 10 feet. Additionally, any attack that would deal damage to the rat king has a 50% chance to hit a nearby swarm of rats instead, taking the damage meant for the rat king. This ability lasts until the rat king chooses to end it as a bonus action, or until all of the swarms it is using as defenders are destroyed or flee.
Reactions
Sacrificial Swarm. When the rat king is targeted by an attack, it can use its reaction to call forth a swarm of rats within 30 feet. If the rat king's AC bonus from the "Swarm Defenders" ability results in the attack missing, the swarm of rats take the damage from the attack, and the attack would have no effect on the rat king. However, if the attack would still hit, both the rat king and the swarm take half the damage from the attack. If the rat king does not have a swarm of rats nearby, it cannot use this reaction.
Rat Swarm Ambush. The rat king can use a bonus action to summon 1d4 rat swarms from the ground, which immediately attack a target within 30 feet of them.
Legendary Actions
The rat king can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The rat king regains spent legendary actions at the start of its turn.
Claw Attack. The rat king makes one claw attack.
Tail Whip (Costs 2 Actions). The rat king makes one tail whip attack.
Summon Rats (Costs 3 Actions). The rat king summons 1d4+1 swarms of rats in unoccupied spaces within 30 feet of it. These swarms act on the rat king's initiative.
Burrow. The rat king burrows underground and can move up to its burrow speed while doing so. It can use its burrow speed to emerge from the ground in any unoccupied space within 5 feet of it.