The Demonic Legions are the polar opposite of the Heavenly Host. While the Army of Light is orderly and disciplined, the Legion uses brute strength and chaos to overwhelm all who stand in its path.
The Demonic Legions are not comprised of a single type of demon, but all the seven Great Evils of Hell contribute to its power. The exact strength of the Legion is not known but they are innumerable and mostly outnumber their foes rather than use their skills to fight. Each Evil contributes a part of his or her army to the Legion, helping it grow. The Prime Evils, being the strongest of the seven, command the Legion as they please against the Armies of Light.
CompositionEditThe Demonic Legion comprises many different types of demons, big and small. They do not follow much discipline but some ranks like the Oblivion Knights and their underlings, the Doom Knights and Abyss Knights seem to be very disciplined. The Abyss Knights, firing their elemental projectiles in deadly synchronization, while Doom Knights rush forward to hack down those who survived the initial bombardment. If that did not decimate their opponents, the commanders themselves, the Oblivion Knights join in the fray, weakening the enemy with deadly curses and shooting very powerful elemental projectiles that can reduce foes to an almost deathly state.
In spite of the organization of some of the ranks, the majority of the Demonic Legion is very unorganized with blood-thirsty demons vying for destruction, waiting to join in battle.
The Demonic Legion appears in Diablo 3 in two of the four Acts, one time in Act III and in all of Act IV. The Legion greatly outnumbers the forces who dare to drive it back. It is said in the game that Azmodan has led the armies of Hell to many victories against the Heavenly Host, and even almost killed Tyrael.
The Siege of Bastion's KeepEdit
Azmodan, the Lord of Sin led many demons to siege Bastion's Keep to retrieve the Black Soulstone. His army was massive, and appeared to be thousands of demons that poured forth from Mount Arreat. The soldiers of Bastion's Keep managed to hold off the Demonic Legion with Archangel Tyrael's command long enough for the nephalem to kill Azmodan and end the invasion.
Fall of the High HeavensEdit
Diablo, the Lord of Terror led the full force of the Demonic Legion into Heaven, and almost manages to destroy the entire Silver City. The angels are completely unprepared for a full scale assault from the demons, and the entire Host is scattered and ravaged. If not for the quick actions of the nephalem hero, the Demonic Legion would have destroyed the entire Heavenly Host and all of Heaven with it.