Ants (or locusts, if implemented) can eat food off the ground, and they create more of themselves when they do, proportional to the nutrition consumed. They can also eat food out of the inventory of something they are attacking, and if the target is carrying food in a bag, they can reach into the bag and either eat the food there or spill it out on the ground. Locusts that can’t find any food to eat could inflict illness with their bite instead. They could also eat grass terrain, if implemented (turning it into normal floor) and multiply that way.

Maybe, to avoid the problem of how unchecked gremlin multiplication creates a bunch of low-HP, one-shottable gremlins, locusts will increase their maximum HP by eating if their own maxHP is below some threshold. (Then they’ll split again by eating more after getting over the threshold.)