Location: This quest can be found in Heliodor – Royal Square.
Objective: Defeat a Harmachis
The Harmachis is located in a plateau south of Hotto Steppe. To reach it, you will need to summon Cetacea using the flute then use her to fly to the Southern Hotto Steppe on the southeastern part of the map. You will need to keep fighting Bilhaws (blue monster in the image above) until the Harmachis (red enemy in the image above) shows up (there is only one Bilhaws located here, but it respawns pretty quickly). Once the Harmachis makes it’s grand entrance, defeat it to satisfy the objective, then return to the old man in Heliodor. Talk with him to complete the quest.
Reward: Apollo’s Axe