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Leech Swarm

Medium · Beast · CR 2 · Unaligned

Source. Tome of Beasts 2

32 (5d8+10)

Ability Scores

Core attributes and their modifiers.

STR

-3

DEX

CON

INT

-4

WIS

CHA

-3

Overview

Category Monsters

Size Medium

Type Beast

Alignment Unaligned

XP 450

Initiative Bonus +3

Movement

Walk 10 ft (3 m)

Swim 40 ft (12.2 m)

Climb 5 ft (1.5 m)

Crawl 5 ft (1.5 m)

Senses

Darkvision 30 ft (9.1 m)

Passive Perception 13

Skills

Perception +3 Stealth +5

Resistances & Immunities

Damage Resistances

bludgeoning, piercing, and slashing

Condition Immunities

charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned

Traits

Blood Frenzy

The leech swarm has advantage on melee attack rolls against any creature that doesn’t have all its hp.

Blood Sense

The leech swarm can pinpoint, by scent, the location of creatures that aren’t undead or constructs within 30 feet of it.

Swarm

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

Actions

Bites

+5 to hit. Hit: 4d6 fire damage.

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 its hp or fewer. If the target is a creature other than a construct or an undead, it must succeed on a DC 13 Dexterity saving throw or lose 2 (1d4) hp at the start of each of its turns as leeches attach to it and drain its blood. Any creature can take an action to find and remove the leeches with a successful DC 13 Wisdom (Perception) check. The leeches also detach if the target takes fire damage.

About Leech Swarm

Leech Swarm is a medium beast with a Challenge Rating of 2. It has a unaligned alignment.

In combat, this creature maintains an Armor Class of 13 and possesses 32 hit points (derived from 5d8+10).

GM Tips: Using Leech Swarm

2 tips available

When using Leech Swarm in your D&D 5e campaign, consider these tactical approaches:

Aquatic Combat: This creature can swim at 40 ft. It has advantage in water environments. Consider fighting on land or using water-based spells against it.
Fire Damage Mitigation: This creature deals fire damage. Advise players to have fire resistance ready or use water-based tactics. Consider environmental fire hazards that could backfire on the creature.

Player Guide: Facing Leech Swarm

2 strategies available

When your party encounters this creature, keep these strategies in mind:

Aquatic Combat Defense: This creature can swim at 40 ft! It has advantage in water. Fight on land if possible. Use 'Control Water' or drain water sources to limit its mobility.
Fire Damage Protection: This creature deals fire damage! Get fire resistance from spells like 'Resistance' or potions. Avoid fighting near flammable objects. Water spells can counter fire attacks.

Encounter Building Calculator

Standard Party Encounter (4-5 characters):

This creature is a medium encounter for a party of 4 characters of level 2.

Solo Encounter:

A single character of level 4 (up to level 20) can face this creature in a medium to hard encounter.

Experience Point Thresholds:

Medium: 600 XP
Hard: 900 XP
Deadly: 1,200 XP

Based on D&D 5e Dungeon Master's Guide encounter building guidelines. CR roughly equals party level for medium encounters.

Frequently Asked Questions

What is the challenge rating of Leech Swarm?: Leech Swarm has a Challenge Rating of 2, making it appropriate for parties of level 2.0.
What type of creature is Leech Swarm?: Leech Swarm is a Medium Beast, which affects how certain spells and abilities interact with it.