Battle for T'krahn
Seeking to increase his wealth Nazdreg, the infamous Bad Moon warlord, sought to invade the planet T'krahn. The planet was infused with precious quartz stones, which were also embedded in crystal structures on the planet. These structures housed the spirits of dead Eldar, which if there was any damage to their integrity, would cast the spirits into the Warp, to be devoured by the Warped Lord of Pleasure, Slaanesh itself. This meant nothing to Nazdreg, who only saw the vast amount of wealth he would claim when the planet was his. Once the Orks invaded, they quickly overwhelmed and annihilated a majority of the Exodites on the planet. The few remaining Exodites went into hiding and were able to use a distress beacon to send a message of warning to the Craftworld Ulthwe. Receiving the message, the Ulthwe responded with amazing speed, braving Warp storms, to get to the planet before the Orks had begun mining.
Striking in strength, the Ulthwe forces, led by the Farseer Eldrad and the Warlock Ardyelle, destroyed the second largest Ork base on the planet. Hoping to end the war quickly, Eldrad sent his forces to locate Nazdreg. The hope was, with his death the leaderless Orks would lose their nerve and flee the planet. It would not be so easy to accomplish though, for Nazdreg's main base was covered in a Kustom Force Field, which ruled out an orbital barrage; and it was located in the Timan Valley, which had steep slopes and was covered in trees and rocky outcroppings, making it difficult to maneuver in and allowing the Orks to easily see anyone who entered the valley. Worse yet, an Ork spacecraft had entered T'krahn's orbit with enough supplies to allow the Orks to engage in a protracted war.
Running out of time, Eldrad quickly divided his forces and sent one half with Ardyelle, to destroy an Ork landing pad they had located. Meanwhile, Eldrad advanced the remainder of his forces into the valley and began to assault Nazdreg's main base. Knowing that if any supplies landed on the planet their efforts to save the spirits of the Eldar would be doomed, Ardyelle and his forces were able to destroy the landing pad after a battle with the Orks guarding it. After it was destroyed, he quickly moved his forces to rejoin Eldrad's fighting in the valley. The battle started badly for the Eldar as the Orks had been lying in wait and ambushed them as soon as they entered the valley. With his forces under fire, Eldrad received a message from the remaining Exodites that the Orks were beginning to mine the crystal structures elsewhere on the planet.
Eldrad knew they had no choice, the Ulthwe would have to weather the Ork onslaught and engage them in order to stop the mining from happening. What followed was a brutal battle, which resulted in the decimation of the Ork forces and the seeming death of Nazdreg himself. With the defeat of their Warboss, the Bad Moons fled T'krahn without mining a single stone.