The crypt spider creates a zombie from a humanoid creature it has killed with its poison. This works like the animate dead spell, except the zombie stays under the crypt spider's control for 1d4 days. At the end of this duration or when the zombie is destroyed, the corpse bursts open, releasing hundreds of crypt spider young (use swarm of spiders statistics). The crypt spider can have no more than four zombies under its control at one time.