La Cucaracha

Roaches roaches roaches roaches
Roaches are drawn to food and eat it (and may spawn near it)
They prefer dark environments and spawn in empty villages, mansions and ancient cities (configurable via tags)
They flee the player when alone, but may attack when in larger group (and if the player is holding food)
Zombies and Skeletons may occasionally drop Roaches
Villagers will sometimes try to crush them, Frogs and Cats will try to eat them
Roaches can be bottled and brewed into a splash potion
Roaches will dance around active jukeboxes

Compatibility