The Mettenheim Renegades are led by Obrist Heynrich, with him being the only spawn of this faction.
This faction is allied with The Kingdom of Ravenstern, The Fierdsvain, the Order of the Dragon, Empire Immortals, the Order of the Radiant Cross and the Order of the Dawn, whilst being at odds with the player (-10), The D'Shar Principalities, the Order of Eventide and all the minor Hateful factions (the ones not in bold), except for the Mystmountain Raiders, the Veccavi, the Melitine Empire, the Vanskerries and the Inquisition, to whom they are neutral. They are also neutral towards all the Knighthood Orders not mentioned before.
It should be noted that the Renegades are not part of the Mettenheim faction and assisting them will not raise your standing with them.