Grunts are the weakest members of the Agency Against Hank Wimbleton. They are the most common enemies in Madness Combat episodes 1-4, after which the agents become more common. They are the simplest-looking characters, with only a gray body and no additional pieces of clothing, accessories or gadgets. They are usually armed with low-ranked melee weapons (pipes, baseball bats, knives...) or low-ranked guns (PPK, TEC-9...) but there are some exceptions. At least one grunt has appeared in every Madness Combat animation, except for Madness Combat 6.5, Madness Combat 7.5, Madness Combat 10: Abrogation and Madness Combat 11: Expurgation.

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