Echoes of Darkness (The Vadelah Chronicles, Book 6)

A seemingly invisible foe is massacring the phantera.

Deadly alien enemies stalk David, seeking to kill him
in the most horrible manner possible. But David soon
learns that Earth is sending him trouble as well.
Between assassinations and kidnappings, one of David’s
friends is brutally murdered. Is this just a foretaste
of his own destiny?