Rat King

October 10, 2023

Medium beast (Swarm), unaligned

Armor Class 14 (natural armor)
Hit Points 52 (8d8 + 16)
Speed 30 ft., climb 30 ft.

STR	DEX	CON	INT	WIS	CHA
10 (+0)	14 (+2)	14 (+2)	2 (-4)	10 (+0)	3 (-4)

Damage Resistances bludgeoning, piercing, slashing
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses darkvision 60 ft., passive Perception 10
Languages —
Challenge 3 (700 XP)

Collapse. When the Rat King is reduced to 0 hit points, it collapses into a swarm of rats.

Keen Smell. The Rat King has advantage on Wisdom (Perception) checks that rely on smell.

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 ft. of the creature and the ally isn't incapacitated.

Swarm. The Rat King can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny rat. The Rat King can't regain hit points or gain temporary hit points.

Actions

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 16 (4d6 + 2) piercing damage. The target must make a DC 12 Constitution saving throw at the end of its next turn or take 10 (3d6) poison damage and become poisoned until the disease is cured. The disease can be cured by any magic that cures disease, but only while the target is not poisoned.

Extension of Rats. Once per turn, the Rat King can extend itself to reach out and make a bite attack against a creature within 10 feet of it. This does not provoke opportunity attacks.

Rat Wave (Recharge 5-6). The Rat King summons a horde of rats to swarm in a 15-foot cone. Each creature in that area must make a DC 12 Dexterity saving throw, taking 21 (6d6) piercing damage on a failed save, or half as much damage on a successful one. A creature that fails the saving throw by 5 or more is also grappled by the swarming rats (escape DC 12). The grappled creature takes 10 (3d6) piercing damage at the start of its turn while grappled. The Rat King cannot recharge this action while grappling a creature.

Swarm of Rats

October 10, 2023

Medium swarm of Tiny beasts, unaligned

Armor Class 10
Hit Points 24 (7d8 - 7)
Speed 30 ft.

STR	DEX	CON	INT	WIS	CHA
9 (-1)	11 (+0)	9 (-1)	2 (-4)	10 (+0)	3 (-4)

Saving Throws
Skills
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses darkvision 30 ft., passive Perception 10
Languages --
Challenge 44930 (50 XP)

Keen Smell. The swarm has advantage on Wisdom (Perception) checks that rely on smell.

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny rat. The swarm can’t regain hit points or gain temporary hit points.

Actions

Bites. Melee Weapon Attack: +2 to hit, reach 0 ft., one target in the swarm’s space. Hit: 7 (2d6) piercing damage, or 3 (1d6) piercing damage if the swarm has half of its hit points or fewer.

Swarm of Ravens

October 10, 2023

Medium swarm of Tiny beasts, unaligned

Armor Class 12
Hit Points 24 (7d8 - 7)
Speed 10 ft., fly 50 ft.

STR	DEX	CON	INT	WIS	CHA
6 (-2)	14 (+2)	8 (-1)	3 (-4)	12 (+1)	6 (-2)

Saving Throws
Skills Perception +5
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses passive Perception 15
Languages --
Challenge 44930 (50 XP)

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny raven. The swarm can’t regain hit points or gain temporary hit points.

Actions

Beaks. Melee Weapon Attack: +4 to hit, reach 5 ft., one target in the swarm’s space. Hit: 7 (2d6) piercing damage, or 3 (1d6) piercing damage if the swarm has half of its hit points or fewer.

Swarm of Insects

October 10, 2023

Medium swarm of Tiny beasts, unaligned

Armor Class 12 (natural armor)
Hit Points 22 (5d8)
Speed 20 ft., climb 20 ft.

STR	DEX	CON	INT	WIS	CHA
3 (-4)	13 (+1)	10 (+0)	1 (-5)	7 (-2)	1 (-5)

Saving Throws
Skills
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses blindsight 10 ft., passive Perception 8
Languages --
Challenge 44928 (100 XP)

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny insect. The swarm can’t regain hit points or gain temporary hit points.

Actions

Bites. Melee Weapon Attack: +3 to hit, reach 0 ft., one target in the swarm’s space. Hit: 10 (4d4) piercing damage, or 5 (2d4) piercing damage if the swarm has half of its hit points or fewer.

Variant: Insect Swarms

Different kinds of insects can gather in swarms, and each swarm has the special characteristics described below.

Swarm of Beetles. A swarm of beetles gains a burrowing speed of 5 feet.

Swarm of Centipedes. A creature reduced to 0 hit points by a swarm of centipedes is stable but poisoned for 1 hour, even after regaining hit points, and paralyzed while poisoned in this way.

Swarm of Spiders. A swarm of spiders has the following additional traits.
Spider Climb. The swarm can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Web Sense. While in contact with a web, the swarm knows the exact location of any other creature in contact with the same web. Web Walker. The swarm ignores movement restrictions caused by webbing.

Swarm of Wasps. A swarm of wasps has a walking speed of 5 feet, a flying speed of 30 feet, and no climbing speed.

Swarm of Bats

October 10, 2023

Medium swarm of Tiny beasts, unaligned

Armor Class 12
Hit Points 22 (5d8)
Speed 0 ft., fly 30 ft.

STR	DEX	CON	INT	WIS	CHA
5 (-3)	15 (+2)	10 (+0)	2 (-4)	12 (+1)	4 (-3)

Saving Throws
Skills
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses blindsight 60 ft., passive Perception 11
Languages --
Challenge 44930 (50 XP)

Echolocation. The swarm can’t use its blindsight while deafened.

Keen Hearing. The swarm has advantage on Wisdom (Perception) checks that rely on hearing.

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny bat. The swarm can’t regain hit points or gain temporary hit points.

Actions

Bites. Melee Weapon Attack: +4 to hit, reach 0 ft., one creature in the swarm’s space. Hit: 5 (2d4) piercing damage, or 2 (1d4) piercing damage if the swarm has half of its hit points or fewer.

Swarm of Quippers

October 10, 2023

Medium swarm of Tiny beasts, unaligned

Armor Class 13
Hit Points 28 (8d8 - 8)
Speed 0 ft., swim 40 ft.

STR	DEX	CON	INT	WIS	CHA
13 (+1)	16 (+3)	9 (-1)	1 (-5)	7 (-2)	2 (-4)

Saving Throws
Skills
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses darkvision 60 ft., passive Perception 8
Languages --
Challenge 1 (200 XP)

Blood Frenzy. The swarm has advantage on melee attack rolls against any creature that doesn’t have all its hit points.

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny quipper. The swarm can’t regain hit points or gain temporary hit points.

Water Breathing. The swarm can breathe only underwater.

Actions

Bites. Melee Weapon Attack: +5 to hit, reach 0 ft., one creature in the swarm’s space. Hit: 14 (4d6) piercing damage, or 7 (2d6) piercing damage if the swarm has half of its hit points or fewer.

Swarm of Poisonous Snakes

October 10, 2023

Medium swarm of Tiny beasts, unaligned

Armor Class 14
Hit Points 36 (8d8)
Speed 30 ft., swim 30 ft.

STR	DEX	CON	INT	WIS	CHA
8 (-1)	18 (+4)	11 (+0)	1 (-5)	10 (+0)	3 (-4)

Saving Throws
Skills
Damage Resistances bludgeoning, piercing, slashing
Damage Immunities
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses blindsight 10 ft., passive Perception 10
Languages --
Challenge 2 (450 XP)

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny snake. The swarm can’t regain hit points or gain temporary hit points.

Actions

Bites. Melee Weapon Attack: +6 to hit, reach 0 ft., one creature in the swarm’s space. Hit: 7 (2d6) piercing damage, or 3 (1d6) piercing damage if the swarm has half of its hit points or fewer. The target must make a DC 10 Constitution saving throw, taking 14 (4d6) poison damage on a failed save, or half as much damage on a successful one.