Dark Apotheosis

Dark Apotheosis is a Demonology warlock spell, gained by choosing Glyph of Demon Hunting.

• Metamorphosis (warlock ability) and Dark Apotheosis share a cooldown, making it impossible to switch between them quickly.
• Doom is not usable, but Corruption is, the same goes for Hand of Gul'dan (usable) and Chaos Wave (not usable).
• Hellfire becomes Immolation Aura (warlock ability), also Nether Plating is active and Carrion Swarm is usable.
• Shadow Bolt and Fear become new spells, Demonic Slash and Sleep.
• Demonic Slash is similar to Touch of Chaos, but it has 3 charges and a much shorter range.
• Sleep puts the target to sleep.

This is a spell given to demonology warlocks who choose the Glyph of Demon Hunting. As one of their main glyphs, it allows a warlock to indefinitely stay in a demon form and use most of the said abilities, including Hand of Gul'dan unlike its more DPS-wise brother. Nether Plating works in this form, the main purpose of this form is mainly for off-tanking in case the tank is killed and the creature is on its last legs but you need a tank. It gives you black and purple demon wings like those in Metamorphosis and once Demonic Fury reaches a certain point it sprouts purple horns as well. Warlocks are incredibly well armored and a warlock using this can pick up the slack left by a dead tank. A skilled warlock who focuses their gear on this ability can tank normal dungeons and, to a limited extent, heroic dungeons as well, however due to the lack of a crit reduction ability, they are not viable for raids.

This does not increase your DPS so it is useless to use it unless you're off-tanking or leveling by yourself against a powerful creature. This also increases the threat of your abilities so if you use it in an instance it'll pull aggro from the tank, which might warrant a kick from the group. However, it is useful in the fact you don't constantly have to cycle between Metamorphosis and your mortal form when you use Demonic Leap it takes the fury but you're technically already in a demon form so this makes you just fly forward without going into Metamorphosis (warlock ability)

In PvP this is likely very viable with the amount of defense it offers overall, and the utility of the abilities within. Demon leaping past your enemy on a hill, or using Sleep on another player to stun them for 8 seconds while you attack the other player. As well as the damage ward and AoE power it offers, it will bring use to warlocks in arenas and such.