Swarm of Spiders

Medium, swarm of Tiny beasts, unaligned

CR 1/2AC 12HP 22 (5d8)

Speed walk 20 ft, climb 20 ft

str: 3; (-4)
dex: 13; (+1)
con: 10; (+0)
int: 1; (-5)
wis: 7; (-2)
cha: 1; (-5)

Damage Resistances bludgeoning, piercing, slashing

Condition Immunities Charmed, Frightened, Paralyzed, Petrified, Prone, Restrained, Stunned

Senses blindsight: 10 ft., passive_perception: 8

Traits

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.

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.

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.