Erinoth's Accelerated Spawning

You place the egg-sack on the chest of a recently slain creature. The creature cannot be a construct, elemental, or ooze. When you cast the spell, the egg-sack embeds itself in the target's chest and matures over the next 1d4 hours. At the end of this duration, a swarm of spiders emerge from the target's chest, rendering the target unable to be revived outside of a wish spell. The swarm is charmed by you for 24 hours, and gains the ability to communicate telepathically if you are within 100ft of the swarm. It obeys all commands the caster gives it. At the end of the duration, the swarm disperses harmlessly.

When you cast this spell at higher levels, you may create two additional swarms of spiders per spell level.