Deathkings of the Dark Citadel

Where Hexen™ ends,

the true nightmare begins

Deathkings of the Dark Citadel picks up where Hexen left off. Having finally obtained the Chaos Sphere, you find yourself suddenly transported to the Realm of the Dead where the sphere is powerless. To escape this unholy, evil world and return to the land of the living, you must journey through a blighted wilderness and lay siege to the mighty Citadel of the Deathkings. In their destruction lies the only passage to true freedom. - 20 new, never-before-seen levels that are darker, deadlier and even more unspeakable than the original Hexen. - Additional levels specifically designed for Deathmatch play (multiplayer mode). - All levels designed by Raven Software, the original creators of Hexen. - Full version of Hexen required to operate. Works with both Windows® 95 and DOS versions of Hexen.

Source:

Back of Box (US)

Having finally obtained the Chaos Sphere, you find yourself suddenly transported to the Realm of the Dead where the sphere is powerless. To escape this unholy, evil world and return to the land of the living, you must journey through a blighted wilderness and lay siege to the mighty Citadel of the DeathKings. In their destruction lies the only path to freedom...

Source:

Developer's website