Lol well NATURALLY
Oh, he was most certainly limitless. The Dark One's power traced back to the actual Holy Grail; drinking from it meant immortality, it also meant that those afflicted with the curse could perform magic above and beyond what 'normal' practitioners could do. His only equal was perhaps Swan, but besides her, Merlin - whom he remembered murdering. Crushed his heart to dust, letting it blow in the breeze for dumbstruck denizens to breathe in. His only weakness was Excalibur, which wasn't even around.
Though perhaps he had another weakness. One right here.
Not that he'd admit it, however. Instead he faced the man who had broken his toys - rude. "Can't even let me have a little fun, can you?" Killian sneered. "What I want is for you to just let me work. But fine."
A ball of fire appeared in his good hand, growing larger. "Your solution is to burn this place down, then? By all means."
It wasn't just a ball of fire that he threw at Hawke - more like a swift torrent of it from the palm of his hand, singing grass and catching on trees.