Can be found at Amos Ship.
Weak against Dimeritium Bomb & Elementa Oil.
Unusually powerful mages can capture and tame these beings. The mage can then draw on its energy, using it to cast spells without having to call on Power from traditional sources. Only a sparse handful have managed this feat, however, for djinns fight to avoid such a fate with stubborn determination. To imprison a djinn and bend it to one's will, one must first weaken it - and that is no easy feat.