The Mountain

"What's the problem?"[...]"It’s a rock." "Well, true,"[...]"That is, unless it starts eating Xians and grows into a Mountain. Still, what are the odds of that ever happening?"

- Mutran and Icarax, The Mutran Chronicles

"The Mountain" was the highest peak on Xia. Unlike all other mountains, this one was actually alive.

History
The Mountain was formed when Makuta Mutran accidentally left his "favorite sentient rock" on Xia while on a diplomatic mission. He figured it wouldn't cause any trouble, but the rock started eating Xians and grew into a mountain.

The Vortixx were expected to climb up the mountain at least once in their lifetime, usually in pairs or groups, to establish their own bravery and ruthlessness. A Vortixx would be especially admired if they returned alone, as they showed how treacherous they could be. One such Vortixx was Roodaka, who left her male companion to die during their rite of passage.

Xia, the homeland of the Vortixx, was an extremely polluted island. However, there was a rumor that the only untainted area of land was the peak of the Mountain. A group of Vortixx set out to prove this, but never returned. They are believed to have been eaten.

The Brotherhood of Makuta once tried to ship some of the rock from the mountain to barricade their own island, but it proved to be a failure after the rock ate the Visorak the Brotherhood sent.

Several large chunks were torn out of the mountain when the Tahtorak and the Kanohi Dragon were fighting. When the Great Spirit Robot was damaged and the Vortixx left Xia, the Mountain was left behind and due to heat and light, it perished.

Tools and Abilities
The Mountain had the power to devour climbers who climbed up its slope suddenly and without warning, which made climbing up the mountain a dangerous task. It could also mold its shape to a certain degree. It would apparently grow when it ate.

The Mountain's structure caused the plants that grow on it to mutate into dangerous, acidic forms, and the skies above the upper portions were said to rain fire; all the better for a challenging trial.

Trivia

 * Acid Grass was a highly corrosive type of plant found on the Mountain.