Crown of Domination

Forged before the dawn of man, the Crown of Domination once held the Eye of Sheerian, but had been lost to history. It strikes terror into the bearer's foes and gives strength to his allies.

Decades after finding the Slayer of Kings, Archaon still had no clue as to the whereabouts of this ancient battle-helm. Eventually Be'lakor revealed its location, planning to steal the crown after Archaon found it.1 p36

The crown lay in the First Shrine to Chaos, high on an icy peak in the Worlds Edge Mountains. Be'lakor led Archaon up the mountain, the Steed of the Apocalypse carrying him over the most difficult terrain. After a day and a half Archaon stood before the massive double gate that was the entrance to the Shrine.1 p36

Through the gateway was a labyrinth filled with dire beasts and vengeful Daemons. Archaon was tested by each of the Chaos Gods to see if he was worthy to be the Everchosen. Nurgle sent deadly diseases that Archaon fought off with sheer willpower. Tzeentch created a labyrinth of crystal, but Archaon blindfolded himself and used instinct alone to negotiate it. Slaanesh sent temptation after temptation, but Archaon resisted, never diverting from the path to the inner gates of the Shrine.1 p36

After passing through the inner gates, Archaon found himself on a narrow causeway surrounded with hellfire that scorched his skin and burnt away his hair. Suddenly, a mighty Bloodthirster of Khorne erupted from the flames and attacked the potential Everchosen. The Greater Daemon was strong, but Archaon drew strength from the Slayer of Kings and wrested the Bloodthirster's weapons away and strangled it with it's own whip.1 p36

The hellfire died away, leaving Archaon standing in a simple shrine. A throne stood at the back of the shrine, with a withered corpse sitting on it. On the top of its withered skull sat the Crown of Domination. Archaon took the crown and, with his wounds healing and frame swelling with power, he held it to the heavens. After over a century of searching, he had claimed the title of Everchosen. All that he needed now was a coronation.

Source

 * Warriors of Chaos armybook