Blueheart Glacier

The Blueheart Glacier is a frozen river that runs through Icewrack. It likely originates somewhere within The Barrier, and flows into the Boiling Sea. Sapphires can be found in the glacier, and are valued by the artisans of the Frostiron Tribe.

The glacier is a conduit for all frost magic in the world, and has its own consciousness which can take on an avatar to interact with others, including those wishing to learn its hidden powers.

Rylai and the Ice Wizard
Tired of dealing with Rylai and her innate ability to freeze everything around her, Rylai's parents sent her off to live in Icewrack. Upon arriving, she met the Ice Wizard at the crown of the Blueheart Glacier, and became his student. The Ice Wizard taught young Rylai how to control her abilities, as well as ice magic. Satisfied with her progress, he descended into the glacier to hibernate, leaving Rylai to watch over the realm. Now learned in the arcane arts, Rylai is able to channel the frosty winds of Blueheart to chill her enemies. Like her mentor, Rylai plans to return to Blueheart Glacier someday, and hibernate for a thousand years.

The Glacier's Heart
According to Rylai, the glacier has a "heart", which is rare and hard to find.

The heart alluded to is likely the Conduit, which forms the crux of its power and is seemingly the source of all magic in the world. It is unknown what relation the Conduit has to the Nether Reaches, which Pugna claims to be the source of all sorceries.

Teachings of the Blueheart
The Conduit passes its teachings onto mortals it finds worthy of taking on the burden of helping maintain the order of the world or, failing that, plunging the world into a new ice age. The training is arduous and takes much more time than most mortals live, and would-be students would often die from the harsh training. The Conduit, holding nothing but indifference toward mortal life, views these deaths with neither joy nor sorrow. Those who do succeed, however, will find their lives lengthened by the Blueheart's magic, and lead a lonely existence in the glacier itself with only books for company. Once their watch has ended, the student will join with the Conduit in death. The Conduit's chosen pupils may also take on students of their own and recommend them to the Conduit's tutelage.

It is likely the Ice Wizard was one of the Conduit's chosen pupils, and passed on some of the Conduit's teachings to Rylai and introduced her to the Conduit. The Conduit believes that Rylai's rivalry with Lina has helped her built up the endurance required to take on its teachings.