Aeratas

Lord Aeratas is introduced as the haughty Alka Alon lord of the fabled lake city of Anthatiel, seat of the Tower of Vision, and one of Minalan's chief opponents on the Alka Alon Council. He openly despises the humani, scorns their possession of irionite, and refuses to commit aid against Sheruel until the Dead God's army is literally at his own gate.

My loyalties cannot be purchased with pretty baubles, Master Minalan.Aeratas, High Mage

Minalan wins his reluctant attention only by gifting him a pendant waystone, and later by leading human magi to break the siege of Anthatiel. When the battle is lost, it is Aeratas who sings the cliffside into the lake and drowns his own city to deny it to Sheruel. Sir Ryff of the Riverlands saves him from gurvani in the plaza — a life-debt Aeratas discharges by pledging his daughter Fallawen to Ryff.

He ends the book an ally in exile, encamped near Sevendor, and grimly aware of what his pride has cost him:

I clung to the glories of the past, thinking I was unassailable because of past greatness and forgotten might. It cost me my city, and nearly my daughter and my life.Aeratas, High Mage

Aeratas does not appear on-page but his transformation is reported by Herus. Following the fall of Anthatiel and the rise of Korbal, Aeratas has become the unlikely leader of a militant new faction of Alka Alon centred on the Ysethary refuge. He openly wears his Tera Alon form in formal council (a scandal among his species), has betrothed his daughter to a mortal, rallies conservative Versaroti, Avalanti, and Farastamari houses to retake Anthatiel, and transforms any Alkan who asks it of him into humanish form for the war.

Your old friend Lord Aeratas is urging them on with renewed vigor. Word on the road is that he sees it as an opportunity to rally support to retake lost Anthatiel. Seeing Aeratas appear in formal council in his humanoid form was scandalous.Herus, Enchanter

Aeratas's largest arc. He moves his Tera Alon army-in-exile to a new encampment near Sevendor (the "Elf's Gap"), arrives at Arth Noafa to press the reluctant Fallawen into honouring her pledge to Sir Ryff, and becomes Minalan's principal Alka Alon partner in planning the raid on Olum Seheri. As the only living Alkan who plumbed the Grotto of Memory and the Chamber of Ages beneath his father's laboratory, he is indispensable to the Scholars team tasked with retrieving the Handmaiden enneagram from the Ghost Rock vein.

This war has barely begun. This is a raid, a chance for revenge and retribution, not an invasion. Trust me: my folk are eager for such a chance. As am I.Aeratas, Necromancer

On the eve of departure he speaks of his own vow:

I shall not leave this world until I have a fitting legacy to bequeath to my own daughter. I will see her rule over a restored Anthatiel, once it has been washed free of its filth.Aeratas, Necromancer

He leads the Scholars down the back stairs into the undercaverns and is the first Alkan in ten thousand years to see the raw Ghost Rock vein:

Behold, the Cavern of Ages. Depository of our ancestors' enneagrams, held within the living stone for all eternity.Aeratas, Necromancer

There he communes briefly with his long-dead wife Hynalinae inside the vein, and is then murdered in the victory celebration by Mycin Amana's necromantic blade. Minalan, using the fresh enneagram imprint Aeratas leaves in the Ghost Rock plus Hynalinae's, resurrects them both into Kulla Alon giant bodies "nearly indestructible" and seals them in the Cavern as its new guardians.

You have my word, Minalan. We will keep Korbal at bay.Aeratas (resurrected), Necromancer

Aeratas is referenced but does not appear. Lilastien tells Ameras:

Lord Aeratas died and then rose again under Olum Seheri, where he protects the legacy there.Lilastien, Footwizard

Minalan reflects on Aeratas as one of the "dour" Alka Alon who once made the humani hope the Alkan old guard had potent secrets to share — a hope now fading with Ameras's revelation that the key to Kova Salainen (the Vault) was lost when the Aronin fell.

A single backward reference during Minalan's return to the ruins of Anthatiel: he recalls "the last desperate and defiant act of Lord Aeratas as we had fled the fallen city: he had flooded the place by plunging one of the cliffsides into the wake." The city, now Olum Seheri, is still in enemy hands and the sacrifice still shapes the landscape.