Advanced Dungeons & Dragons 2nd Edition Wiki

The swarm of small animals (roll on following table to determine type, or the DM can assign an appropriate creature) drawn by the summon swarm spell will viciously attack all creatures in the area chosen by the caster.

Creatures actively defending against the swarm to the exclusion of other activities suffer 1 point of damage for each round spent in the swarm.

Those taking other actions, including leaving the swarm, receive damage equal to 1d4 points + 1 point per three levels of the caster, every round. Note that spellcasting withing the swarm is impossible.

A d100 roll of 01-40 will summon rats.

A d100 roll of 41-70 will summon bats.

A d100 roll of 71-80 will summon spiders.

A d100 roll of 81-90 will summon centipedes/beetles.

A d100 roll of 91-100 will summon flying insects.

The swarm cannot be fought effectively with weapons, but fire and area effects can force it to disperse by inflicting damage. The swarm disperses when it has taken a total of 2 hit points per caster level from these attacks.

A protection from evil spell keeps the swarm at bay, and certain area-effect spells, such as gust of wind and stinking cloud, disperse a swarm immediately, if appropriate to the swarm summoned (e.g., only flyers are affected by a gust of wind).

The caster must remain stationary and undisturbed to control the swarm; if his concentration lapses or is broken, the swarm disperses in two rounds. The swarm is stationary once conjured.

The material component is a square of red cloth.