Legion raids completed (final boss defeated)

Details

WhereThe Emerald Nightmare (entrance in Val'sharah at 56.3, 36.7)

2 criteria from the current game data. Not every line is required; the description above states the goal.

Lines the game data counts toward this achievement.

Where: The Emerald Nightmare, The Nighthold

XaviusOnce a powerful mage, and a councilor to Queen Azshara, Xavius forged a pact with Sargeras to enable the Legion's first invasion of Azeroth. Cursed and tormented in the wake of that defeat, Xavius plots vengeance against the world from within the Rift of Aln. Those who venture into the Nightmare will face the full extent of his power, and his true form - a grotesque and distended monstrosity.
Gul'danThe chain of events set in motion when Garrosh escaped to Draenor has continued, unbroken for all its twists and turns, leading to this very moment. Thwarted in Draenor, Gul'dan now stands on the precipice of achieving ultimate victory on behalf of his Legion masters. Standing atop the Nighthold, as the vortex of fel energy swirls in the skies overhead, the outcast orc warlock awaits his destiny.

Legion raids completed (final boss defeated) is earned inside The Emerald Nightmare. The entrance is marked below.

The entrance to The Emerald Nightmare is in Val'sharah at 56.3, 36.7.

Val'sharah, from the game’s own world map art. The framed marker is the Adventure Guide entrance.

Other achievements whose criteria ask for the Xavius encounter.

Other achievements whose criteria ask for the Gul'dan encounter.

Other achievements in Dungeons & Raids.