Antrax

Fearless adventurers guided by Walker Boh, the last Druid, traversed uncharted waters in pursuit of a fugitive sorcery. However, it now seems that Walker and his group were drawn there for nefarious, unanticipated reasons. The enigmatic Ilse Witch is pursuing Bek Rowe, the Druid's pupil, and his friends as they flee the wicked forces attacking the crew of the airship Jerle Shannara. In the meanwhile, Walker finds himself abandoned, pursued by an invisible, ravenous foe, in a pitch-black labyrinth under the destroyed city of Castledown. It is not human, yet it is alive and lusts for the power of elves, Druids, and even the Ilse Witch. For its own purposes, it pursues mankind. It's Antrax, the ghost who eats magic and ensnares men's souls. And with it, the Four Lands' future is in jeopardy.