Heruka couldn't yet tell how Mithras' Vanity worked, but the energy signature didn't escape the ancient deity's senses, enabling him to figure out that he faced an Idol of Vanity: the Idol of the Sun!
Pyrogasmic Genesis and all divine-class Inner Flames that the Red God had accumulated over the years became food for Mithras' light, boosting his Sid Level at an alarming rate while adding new attributes to Solar Genesis!
Even the Wrathful God Fire now worked in reverse, threatening to roast the Red God from the inside out! For the Wrathful God of War, number one Ero Guru of the Higher Planes, there could be no greater humiliation, no greater shame, than losing his Inner Flames to a junior. The same junior who threatened to hijack the Chosen he'd wasted countless boons to create!
[Inner Alteration]
The Red God closed his eyes, pulling in a deep breath as the Fourth Secret kicked in—cooperating with the Wrathful God's quasi-perfect healing factor to suppress the internal combustion and repair his body. A red prism formed around the Wrathful God Fire, isolating it to prevent another flame trick from taking the Red God by surprise.
Heruka's eyes opened again, a colossal pair of flaming red horns sprouting from his forehead as he hurtled at Mithras!
[Writhing Shadows of Calamity]
[Occult Revelation: Nihilistic Creed of Anarchy]
With dark-purple energies bursting in his right hand, and a vortex of pitch-black forces in his left, Mithras joined his hands in a prayer sign, casting two Dark Rites simultaneously. Colossal shadows clawed out of the void, fusing into a mass of writhing darkness that swept through the Red God and ground his charge to a halt.
Still, Heruka didn't relent, pulling in another breath...and blasting through the Shadows of Calamity with brute force alone! The moment next, Heruka turned into a red flash of light, blitzing Mithras through Quantum Tunneling and ramming his horns in his grandson's chest!
Mithras neither dodged nor blocked, countering with a flying knee as parasitic worms of corruptive darkness burrowed out of Heruka's organs, eating them from the inside!
Heruka's world spun, and his charge collapsed—all momentum crashing to zero as the Red God spun left and right! Mithras' flying knee smashed into Heruka's skull, battering face and bones as legions of occult parasites crossed into Heruka's soul, spawning eggs of Nihilistic Demons wherever they went, and causing tides of foul energies to corrupt Heruka's body and soul.
The Red God shrugged it all off, smashing into Mithras' jaw with a spinning back fist! He didn't see it coming, his jaw cracking and his blood spurting as he whirled like a spinning top. Heruka appeared above Mithras, ax-kick sinking into his grandson's skull as the Third Secret kicked in, increasing the weight of Heruka's leg to planetary proportion.
Tough as Mithras might be, a blow of that magnitude would no doubt leave debilitating damages. But a moment before the kick hit home, Mithras broke into light particles, reforming a microsecond later in the very same spot, with his leg now spinning at Heruka's throat—lacerating the Red God's neck with one swipe!
Once more, Heruka's willpower made a show of force, and he shrugged off the pain, hammering Mithras' ears with a flurry of open-palm strikes. The blink of an eye was all it took for a myriad of blows to blast through Mithras' eardrums, blood trickling down his lobes as the Red God's herculean flaming fists raced towards his chest!
The Sixth Secret, Nirvana, operated as well, creating a solution to Heruka's most pressing issue—the occult parasites—and reducing them to ashes with a flash of transcendent energies.
Heruka couldn't see the white-haired figure's eyes, yet could feel their stare piercing through him, able to decide his life and death at will!
Even Mithras didn't notice the intrusion. The figure didn't linger, vanishing the moment next—yet with that one look, had discouraged Heruka from attempting that suicidal move.
[Worldbreaker]
With a low, grating roar, the Red God threw his mangled head back, activating a divine-class talent that Mithras had only faced in Belphegor so far.
But in Heruka's hands, that divine talent reached abnormal proportions, ripping the very fabrics of the world as it sent Mithras flying with pressure alone!
Heruka returned to his feet, ballooning to a 100 meters as he stomped his foot, cracking the foundation of Mithras' Mandala and barreling through his defenses with irresistible force!
"Mhm...isn't that talent proof you have the Beast's blood flowing through your veins? Shameful thing. To think that you'd betray the Beast to become the Weaver's lapdog. Heru-jiji, I'm disappointed.
As far as grandfathers go...you are a generational failure," Mithras said in a leisurely tone, and as Celestia wondered where he was getting that confidence from, Mithras threw his hands in circular motions, channeling Solar Genesis, and spreading its flames...across the whole Mandala!
"What...do you think you're doing here?" A sense of foreboding welled up Heruka's chest, and he backpedaled, convinced by his instincts that if he didn't vanish this very instant, a tragedy was heading his way.
But with his chosen still under Mithras' thumb. Even if his brain told him to, Heruka...couldn't leave!
"Completing...my thesis," Mithras said in a cheerful and nostalgic tone, throwing his head back as his hands weaved like a maestro.
So far, Mithras' Pyromantic Thesis couldn't alter the world, just its lifeforms. But as his fingers danced and his blinding flames unfurled, Mithras broke through the final barrier, learning from his Mandala, Heruka's Outer Alteration and Divine Fantasy...to Alter the World Through Flames!
Colossal tongues of fire reshaped the heavens and earth, casting glorious solar temples from which droves of Lion-Headed Serpents emerged, followed by legions of slimthick nagas, ancient wyrms and other reptilian creatures that aligned behind Mithras, feeding him their energies as they sang the praises of the Sun.
The Million Snakes of the Burning Hell arose, ripping through Heruka...and reducing him into ashes!
[Ding! Ding! Ding!]
[Pyromantic Thesis...completed!]
[Achievement....Flame Professor...unlocked!]