Domains: Mountains, high places, ascent.
Era of ascension: Golden Age of Man (~155,000 years ago). Cohort: dead. Died: God War & Long Winter (~75,000 years ago), when the high passes filled with ice that never melted again and the pilgrimage routes that anchored her worship were lost beneath them.
Worshipped by: The montane civilizations of the Golden Age — Alpine and high-plateau polities whose calendars were keyed to the spring opening of the passes — and the peak-shrine pilgrimage traditions whose rite was the climb itself. No living culture maintains her worship. (The worships edge is authored downstream on the worshipper, not here.)
Belláath was the vertical. Drevun owned the stone as material — the geology of endurance, the weight that did not move — but Belláath was the act of going up the stone. Her worship was the pilgrimage: a route, a season, a permitted month, a marked stopping-place at each thousand feet of climb, and a small shrine at the summit where the rite was completed and the climbers turned back. The doctrine held that the rite required the round trip; a death on the descent was the climb completed; a death on the ascent was the climb refused. The high polities calibrated their summer calendars around her shrine-windows the way river polities calibrated theirs around floods.
The Long Winter took her by the passes. Within a single decade the routes were impassable; within two, the snow on the routes was no longer seasonal but permanent; within three, the high shrines were buried under a depth no mortal would ever clear. Her last priesthoods kept records in the valley towns of where the routes had run, in the expectation that the cold would break and the climbs would resume. The cold did not break and the records went into the libraries Graelith could no longer protect. The shrines remain under the ice they were buried in.