Breeding Pit

{t}: Create a 0/1 rat token named "Brood
Mother" which has: "{t}: Create X 1/1 rats
where X is half the number of food you
control rounded down."

"While some broodmothers are vaunted, such as
the bearers of Stormvermin and other
higher-caste specimens, the majority are kept in filthy pits."