3.Lest Dawn Fail.n-Wekesa

More than an hour had passed since then, Wekesa thought, and he idly adjusted the bubble of force around him to dampen sound as the peak to his left exploded.

...

A storm brewed in the sky above them, this one not of his making. He could feel it strengthening, the lightning concentrating in a killing stroke she would cast down when she found him. Her casual shattering of mountaintops was an attempt to flush him out, though an unsuccessful one so far.

...

It had been wise precaution to mute sound, Warlock decided, for the howl of wind was deafening. Lightning thundered down, hundreds of strands, and flashing lights danced across the peaks. The roar of avalanches by the dozens devoured the rest of the song and he laughed, runes shining around his wrists as he wove the lightning into spears and struck at the Witch. The murderous child took it in stride, force spinning around her and making a wheel of the power he sent at her. She released it when his strikes ebbed, released a ring of pure lightning that shattered another two peaks.

...

The last word from the Ninth was that Sacker had lost over seven hundred to an avalanche. While a mile away from the duel of the mages. Her entire rear guard swallowed by rocks, along with more than a few engines. In the northern valley, the costs had been no less steep. The mage officers of the Tenth had still been in the mountains when the two Named had begun slinging their spells, and half of them had been lost making their escape even as the battle around the Proceran camp erupted. The matron had forgot quite how terrifying Warlock could be, when let loose, but for all that terror the Witch had been every bit his match. And in their struggle, they had wrecked the Vales beyond recognition. The southern Twin was buried in stone along with most the valley before it, while a stray lance of lightning had hit the peak above the northern one, making half the mountain collapse atop it. That alone would not have cut retreat entirely for the Legions, but then Warlock had begun throwing down mountains to replace those he’d broken and it had gotten much, much worse. Half a city’s worth of brimstone had tumbled down the slope of the northern valley after being batted aside contemptuously by the Witch of the Woods, and there was no going around that.

- Book 3, Interlude: Lest Dawn Fail