Stone of Farewell

Book 2 of Memory, Sorrow, and Thorn. First published in 1990
It
is a time of darkness, dread, and ultimate testing for the realm of
Osten Ard, for the wild magic and terrifying minions of the undead Sithi
ruler, Ineluki the Storm King, are spreading their seemingly
undefeatable evil across the kingdom.
With the
very land blighted by the power of Ineluki’s wrath, the tattered
remnants of a once-proud human army flee in search of a last sanctuary
and rallying point—the Stone of Farewell, a place shrouded in mystery
and ancient sorrow. 
An even as Prince Josua seeks to rally his
scattered forces, Simon and the surviving members of the League of the
Scroll are desperately struggling to discover the truth behind an
almost-forgotten legend, which will take them from the fallen citadels
of humans to the secret heartland of the Sithi—where near-immortals must
at last decide whether to ally with the race of men in a final war
against those of their own blood.