If magic could be devoured, it stood to reason that Ki might also be devoured.
Therefore, Goku didn't start by unleashing his high-stamina-drain energy waves. Instead, he opted for a close-quarters melee assault to test the waters.
He needed to see if his Giant Form combined with Total Concentration Breathing was capable of dealing actual physical damage to the Black Dragon.
BOOM!
Goku's foot slammed violently into the dragon's snout. The sheer force made the standing Acnologia stumble back, nearly losing his balance.
"What incredible physical defense!"
Goku landed his hit but didn't immediately follow up. Instead, he pulled back with a grim expression to regain distance.
The first strike was a probe, and the results were clearly not good. A full-force kick in this state had only managed to make the dragon stumble; it hadn't dealt any substantive damage.
However, that kick was more than enough to enrage the Black Dragon.
With a thunderous roar, Acnologia spread his wings and turned into a streak of black light. He lunged toward Goku, his razor-sharp claws extended, seemingly intent on shredding the boy in two on the spot.
"6th Form! 7th Form!"
Goku utilized the 6th Form of his breathing style to heighten his kinetic vision, allowing him to track the dragon's blinding speed. He followed up with the erratic footwork of the 7th Form, narrowly evading the dragon's claw.
"4th Form!"
The moment he dodged, his right fist erupted with tiger-shaped Ki, hammering down toward the dragon's side.
External energy attacks might be devoured by the dragon, but techniques that internalize energy to augment the physical body still worked—this was why Makarov had been able to restrain the dragon's neck earlier using Giant Magic.
By layering internal physical-enhancement magic with his martial arts, Goku traded blows with the dragon.
The observers below could only hear a continuous, rhythmic booming and catch glimpses of the two titans clashing in the sky. To avoid the shockwaves, the guild members were forced to retreat further and further.
"He won't win."
Zeref, also maintaining a safe distance, sighed once again.
On the surface, it looked like a back-and-forth struggle, but Zeref knew the truth. It was only because the dragon hadn't exerted his full power.
Likely, the boy's prowess had piqued Acnologia's curiosity, making him willing to play for a bit longer.
But Acnologia was not a dragon known for patience; he would soon grow bored and proceed to annihilate every living soul in sight. He was, after all, the Black Dragon born for Apocalypse.
Sure enough, it wasn't long before Goku's figure was sent crashing heavily from the sky. Blood soaked his chest where the dragon's claws had torn through his skin.
"You really are amazing!"
Goku pushed himself off the ground, gasping for breath, yet his eyes were burning brighter than ever.
He had just used his full power and was still outmatched; the dragon was truly an entire tier above him. Furthermore, Acnologia had only used his raw physical strength so far, without even dipping into his racial dragon magic.
"Even though I know you can devour magic, I still have to try!"
Goku looked up at the dragon hovering in the sky. He dropped into the stance for the Kamehameha.
In the eyes of this world, the Kamehameha was a "spell," but Goku knew better. It was a martial arts technique created by Grandpa Roshi.
While Ki and Magic were compatible, they were fundamentally different.
"Devouring Magic" could reduce a spell to Ethernano, but it wouldn't necessarily be as easy to deconstruct a Ki-based energy wave. He had to know.
"Kamehame—HA!"
The moon-shattering energy wave erupted from Goku's palms, roaring straight toward the dragon.
Acnologia didn't dodge. Disdain flickered in his eyes. To him, no matter how powerful a spell was, it could not harm him. He reflexively applied his devouring properties to his skin.
The Kamehameha slammed into him. Unlike other spells, it didn't instantly dissolve into Ethernano.
About 90% of the wave was neutralized by the devouring effect, but the remaining 10%—the part the magic couldn't deconstruct in time—slammed into his hide.
For the first time in centuries, Acnologia felt a spark of pain. The last time he felt this was during the Great Dragon Civil War.
"Strange magic... it offers so much resistance to my devouring," the dragon thought, his confusion quickly turning to fury.
He was confused because he had never encountered energy so difficult to break down, and he was furious because a mere "ant" of a human had actually wounded him.
"Black Dragon's Roar!"
Aiming down at Goku and the assembled humans, he decided to erase the ant that dared hurt him along with everyone else.
Seeing the black pillar of energy descending, the Fairy Tail wizards fell into despair. If even Goku's most powerful attack couldn't stop the dragon, what hope did they have?
Zeref shook his head and prepared to teleport away; he felt they were all beyond saving—even Natsu.
In the shadows, Mard Geer was nearly paralyzed with fear, caught between the apocalypse dragon and his own creator, Zeref. He hid as deeply as possible, terrified of being noticed.
"Don't give up! Let's pool our power together to help Goku! Let this guy see the bonds of our guild!" Natsu roared. The despair in the wizards' eyes was replaced by fierce determination. They wouldn't sit and wait for death.
"Goku hasn't used his full power yet. No need to worry," Dumbledore said. Though his expression was grave, he hadn't lost hope. He knew Goku had one more card to play: the Animagus transformation.
Just in case, Dumbledore pulled out a Portkey—a book that, once opened, would whisk everyone back to Magnolia instantly.
"You're really strong. I guess I need to keep training hard," Goku muttered, watching the sky fall. As the roar approached, he activated his Animagus transformation.
A terrifying howl erupted. Goku's ten-meter frame expanded violently, swelling into a hundred-meter-tall Saiyan Great Ape.
With a sudden, explosive leap, he lunged straight through the pillar of black energy! He crashed into the airborne Acnologia, grabbing the dragon's neck with a massive paw and slamming him into the ground.
Then, a hurricane of punches began to rain down on the dragon.
Acnologia roared and struggled, flapping his wings to take flight, but each time Goku grabbed him by the neck and slammed him back into the earth.
At one point, Goku seized the dragon's tail and began swinging him back and forth, smashing him against the terrain.
In terms of pure physical strength, the Black Dragon was no match for a Saiyan Great Ape empowered by both Giant Magic and Total Concentration Breathing.