My yapping for anyone that would be interested:

Argos, the bastard king: The crowned prince of his clan and last member of his kind, a cannibalistic, brutish man possessing monstrous potential and immense raw destructive capacity thanks to inheriting his father's immense magic affinity, and having the blood of the ancients running through his veins. Standing at about 2.6 meters in height, he towers over any who dare stand in his way, crushing, devouring, or pulverizing those he deems responsible for the destruction of his clan. As a testament to the sheer might of his lineage, in a mere 80 years of existence, Argos has managed to surpass the prime of his terrifying father, Argus, someone who used to be referred to as a grand sage and the terror of the east, having gathered the raw power needed to almost rival the 900 years of history that The lord of Salt Mountain has accumulated. His legions of humanoid golems, shaped in the image of the members of his clan that he remembers, are part of what he calls "the wonderfully mysterious forests", a culmination of both lost technology and the archaic arts, capable of self-repair, flight, and destructive capacity slightly higher than Argos himself; this superweapon is his trump card against any force that would dare to oppose him, and the main reason for why he hasn’t been caught despite the disasters he has caused. 

Physical description: A muscular pale giant clad in plate armour reminiscent of bronze, yet made of an infinitely superior material. His long black hair cascades freely down his back; his sharp charcoal eyes stare down with arrogance at those unfortunate enough to encounter him. If not for his unkempt appearance and his deeds, some may say he even looks graceful. 

Alignments: Lawful evil with occasional bursts of chaotic evil, and in some cases, small acts of kindness, directed towards individuals whose predicaments touch what little is left of his empathy. His main purpose, which has influenced his actions, is to ascend to near proto-godhood, which he believes would grant him the power needed to drag the past into the present and bring back at least some members of his dead clan; for that reason, he wants to consume Salt Mountain and assimilate his power into his own. Argos has the odd habit of either finding a way to hide his presence, or making his entrance as theatrically grand as possible, with an example being that one time he came crashing down onto a band of mercenaries while riding a meteor. 

Fun facts: Argos enjoys blacksmithing, viewing the act of crafting artifacts as a relaxing task that stimulates his mind as he ponders over his plans, and he is good at playing pipe organs, enjoying putting on a dramatic show in the background as he reads or spends his time causing mischief. He tends to collect the skulls of opponents he either respected or particularly despised, with the habit of turning some of said skulls into mugs from which he drinks a black tea so strong it could kill a lesser man. Though no person has been dumb enough to get close enough to observe this, Argos often has one-way conversations with both his collection of skulls and the golems of his fortress. 

Long story short, Argos manages to steal 3 starts of prophecy from The lord of salt mountain, metaphysical objects that can be used as the means through which the sorcerer's soul and ego can be reborn in case of death, or to influence events on a larger scale by making one specific event in the future the most likely outcome. He consumed 2 of the 3 stars to amplify his power and understand their inner workings, then used the 3rd to kickstart his ritual by turning the entirety of his wonderfully mysterious fortress as his altar. Consuming the power within the fortress and the strands of his soul stored within the golems, he forcefully pulled the land of dreams into the material universe, turning the wonderfully mysterious fortress into his innate domain, which he then fused with the seat of power of Ares, a dead god of war and bloodshed. Using that amplified and then further amplified power he tried forcefully ripping the souls of his clan out of purgatory so that he could stuff them inside the golems and grant them a new life, but all of that power and the rift between the land of dreams and the material universe attracted The abhorance and allowed it to break into the world of the living.

How did your major antagonists have their plans fail after almost succeeding?