Iron Knuckles (鉄挙隊 (アイアンナツクル) Aian Nakkuru; Iron Fist Regiment), is a clan whose members call each other "bros" (兄弟たち (ブロズ), burozu; brothers). The members do not use their real names. It is unknown how many members Iron Knuckles has but they were able to field 20 members in the attack on the white giant god in the Dusk Realm. The clan symbol is a clenched fist and their colors are blue and black.
They have a good relationship with the Berserkers.