Cabbage

Vegetables. Some move around and are treated like monsters. In this world, a characteristic of vegetables in general is that fresh ones can move around, and in the case of cabbages, they can hop and fly through the air with their leaves. Sometimes, they are mixed with lettuce, and Aqua, due to her bad luck, mostly harvested lettuce.

When the season comes, they leave the fields and form countless groups to move around different areas, and the adventurers of Axel town capture them to "harvest" and trade them at high prices, with the price increasing with the experience points a single cabbage can offer (Kazuma, thanks to his good luck, harvested an amount equivalent to 1 million Eris). The group charges are somewhat of a threat, and the general populace evacuates.

When subdued, the cabbages trampled the participating adventurers and even destroyed Darkness's armor with a body slam, but were wiped out by Megumin's explosion magic. Afterwards, soaked in water by Aqua's magic and the guild's people, they were preserved, cooked into various dishes, eaten, or sold as subjugation rewards.