Lord of Vermin
While ordinary druids have authority over companion animals and the beasts around them, Vermin Lords command swarms of vermin. Rats, bats, and ravens flock to them, and Vermin Lords are never found without spiders or other creatures in their hair and clothes. They can even Wild Shape into a vermin swarm.
-How it Came to Be
2-3 Lines of why Lord of Vermin Exists-
Unique to the Mixture
Wild Shape into a swarm is a trait unique to this class. Vermin Lords also attract swarms very quickly and (after level 2) can gain a new swarm at a short or long rest. Commanding a swarm is very useful as the swarm’s AC is fairly high due to the small size of the component vermin, yet its total damage is also respectable.