Swarm, Spider (CR 1)

Diminutive Vermin (Swarm)
Alignment: Always neutral
Initiative: +3 (Dex); Senses: darkvision 60 ft., tremorsense 30 ft., Listen +4, and Spot +4


AC: 17 (+4 size, +3 Dex), touch 17, flat-footed 14
Hit Dice: 2d8 (9 hp)
Fort +3, Ref +3, Will +0
Speed: 20 ft., climb 20 ft.
Space: 10 ft./0 ft.
Base Attack +1; Grapple -
Attack: Swarm
Full Attack: Swarm
Damage: Swarm 1d6 plus poison
Special Attacks: Distraction, poison
Abilities: Str 1, Dex 17, Con 10, Int -, Wis 10, Cha 2
Special Qualities: swarm, vermin, immune to weapon damage
Feats: -
Skills: Climb +11, Listen +4, and Spot +4
Advancement: -
Climate/Terrain: Warm forest
Organization: Solitary, tangle (2-4 swarms), or colony (11-20 swarms)
Treasure/Possessions: None

Source: Monster Manual

A horrible, scuttling army of hand-sized spiders scrambles forward.

A spider swarm is a scuttling horde of venomous spiders.

Combat

A spider swarm seeks to surround and attack any living prey it encounters. A swarm deals 1d6 points of damage to any creature whose space it occupies at the end of its move,

Distraction (Ex): Any living creature that begins its turn with a spider swarm in its space must succeed on a DC 11 Fortitude save or be nauseated for 1 round. The save DC is Constitution-based.

Poison (Ex): Injury, Fortitude DC 11, initial and secondary damage 1d3 Str. The save DC is Constitution-based.

Skills: A spider swarm has a +4 racial bonus on Hide and Spot checks and a +8 racial bonus on Climb checks. It uses its Dexterity modifier instead of its Strength modifier for Climb checks. It can always choose to take 10 on a Climb check, even if rushed or threatened.