Mal'Ganis was one of the nathrezim sent by Archimonde as a jailor of the Lich King. He was chosen to head up the plot to turn Prince Arthas to darkness, and make him the Lich King's greatest champion.
This section concerns content exclusive to Warcraft III.Mal'Ganis in Warcraft III.
As Arthas and Jaina Proudmoore were investigating rumors of plague, they were attacked again and again by the forces of the Scourge posing as the personal army of the dreadlord Mal'Ganis. Kel'Thuzad helped play the part by telling Arthas that it was Mal'Ganis himself and not the Lich King behind the plague. Each attack, each town destroyed hit at Arthas' weakness, his pride. Arthas began to take his inability to protect his people from the Scourge personally, and soon became obsessed with killing the dreadlord.
Mal'Ganis led Arthas to Stratholme, and left him with the choice of either slaughtering all of its inhabitants or watching them fall to the plague. Arthas chose to kill his own subjects rather than let them become slaves to Mal'Ganis in death, killing most of the inhabitants of the town. Mal'Ganis was there in the wreckage, and goaded Arthas once again to come to Northrend to finish their battle. As expected, Arthas took the royal fleet and sailed north. The Prince's obsession with the hated dreadlord led him further down the path of evil, first lying to his men, betraying his mercenaries, and finally forsaking his own soul to take up the runeblade Frostmourne, grievously wounding Muradin Bronzebeard in the process.
The moment Arthas took up Frostmourne he became a tool of the Lich King, completely subservient to his will. This was what Mal'Ganis had planned all along. Confidently he approached Arthas and informed him of his fate. However, the manipulative and traitorous dreadlord was himself betrayed, as the Lich King's first whispers to Arthas were that the time for his vengeance had come (this was the first step towards Ner'zhul's independence). Arthas defeated the dreadlord and believed him to be slain.
Mal'Ganis is the final boss in the Stratholme of the past, the fourth wing of the Caverns of Time that opened with the release of World of Warcraft: Wrath of the Lich King. In the Warcraft III scenario The Culling, Mal'Ganis would always resurrect after a certain period and return to continue his corruption of the city. In the instance, however, once Mal'ganis is taken to 1% health, he teleports out of the city after telling Arthas to meet him in Northrend.
Memorable quotes
Mal'Ganis in WoWMal'Ganis in Warcraft III.
Encounter in Stratholme
"I've been waiting for you, young prince. I... am Mal'Ganis."
"As you can see, your people...are now mine! I will now turn this city household by household...until the flame of life has been snuffed out...Forever!"
Taunting Arthas in Northrend
"The Dark Lord said you would come! This is where you journey ends...boy. Trapped and freezing at the roof of the world, with only death to sing the tale of your doom!"
Mal'Ganis' last conversation with Arthas, a few seconds before his presumed death...
Mal'Ganis: "So, you've taken up Frostmourne at the expense of your comrade's life... Just as the Dark Lord said you would, you're stronger than I thought."
Arthas: "You waste your breath Mal'Ganis... I heed only the voice of Frostmourne now!"
Mal'Ganis: "You hear the voice of the Dark Lord. He whispers to you through the blade you wield... What does he say, young human? What does the Dark Lord of the Dead tell you now?"
Arthas: "He tells me the time for my vengeance... Has come!"
Mal'Ganis: "What? He can't possibly mean to -" (Arthas swings his blade at Mal'Ganis)
Arthas: "It is finished!"
Encounter in Icecrown Glacier in the Onslaught Harbor
44-54 hero melee damage (same as a regular dreadlord)
6 hero armor (same as a regular dreadlord)
Attributes
42 Strength Primary Attribute(same as a regular dreadlord)
25 Agility (same as a regular dreadlord)
40 Intelligence (same as a regular dreadlord)
Abilities
Carrion Swarm (multiple target damage in a line)
Sleep (incapacitates enemy)
Dark Conversion (turns a villager undead)
Soul Preservation (sends undead unit to the "nether-realm")
Trivia
Though plotting his revenge upon the Lich King, developers hinted that he would have no role in Icecrown Citadel.[1] This eventually proved true. Mal'Ganis is nowhere to be found within Icecrown Citadel.
In the final level of The Scourge of Lordaeron in Warcaft III: Reign of Chaos, using the given base and units it is possible to invade and destroy Mal'Ganis' base, but if Mal'Ganis is killed before Arthas returns with Frostmourne; Mal'ganis will drop 2-3 [Ankhs of Reincarnation], and come back to life. This can be repeated numerous times and when he does finally stay down (you will see the death animation when he finally dies), Ankhs will continuously spawn from where he died.