They're aetherial cartridges used in my combat style. It is defensive, primarily, but these increase my offensive capability. It doesn't rely upon as much aether -- mana, that is, -- as a Caster.

[Not a slight, just a matter of fact. And a subtle indicator that he knew what Caster was. It was said while shooting a lightning shot into the group of Fae making them scatter. Shake them long before they try to shake him.]

On the contrary, what I've heard has been complimentary. But I wished to confirm that we were of the same mind for myself. [Another shot from his blade, this time towards the air which seemed to form a shield around Caster.] You are protected. They'll not interrupt your spells.