Slugs

A Phagan Slug is a genetically engineered time bomb for world crystals.

Created by the Phage utilising their understanding of the Seeders magitech, the slugs were developed to infect and consume world crystals, preventing any resurgence of the Seeder race.

A Phagan Slug is basically a massive Aboleth. They are capable of interstellar travel but such activity consumes immense amounts of energy. Having travelled to a world, the slug will consume it in preparation for its next interstellar flight.