Iron Judge

The Iron Judge Archibald Iman, of the Mage King Triad, administers justice to the Mage Kingdom. Like many of the others in the kingdom, he was given an amulet that lets him draw upon the Mage King's power of Free Magic. His spells are mostly related to capturing or subduing opponents, not killing them, although he still has formidable power when against opponents he means to kill.

He travels with his assistant Piper Poll, and has (presumably) taken her on as a protegé, as she uses similar spells.