Normally, humans breathed oxygen at a concentration of 21%.
When the oxygen concentration rose to 40%, Accelerator began to feel unwell.
His chest felt tight, and he had a strong urge to cough. But his body had always been frail, and such symptoms were common when he fought at full strength.
It was like someone lacking exercise running a hundred-meter sprint—the sensation was exactly the same as the early symptoms of oxygen poisoning. Thus, Accelerator noticed nothing.
Soon, his lungs developed a distinct burning sensation. Breathing became noticeably difficult, and he could no longer suppress the urge to cough, breaking into loud, violent coughing.
Accelerator displayed severe respiratory distress syndrome. The intense coughing disrupted his concentration, and his attacks immediately weakened.
Misaka Shazo chuckled twice. "Misaka happily tells the foolish Accelerator: Idiot, you don't know how you're being attacked, do you?"
"Misaka says expectantly: Experience Misaka Shazo's super invincible saturation attack."
Countless Ionized Magnetic Field arrays appeared within a hundred-meter radius around Misaka Shazo. The densely packed arrays captured iron nails, sand, leaves, dewdrops condensed by shockwaves, and more.
The Ionized Magnetic Fields gave these substances ionized positive and negative charges, then fired them as bullets.
The energy intensity of each Ionized Magnetic Field was not high, so the bullets' initial velocity was not particularly fast—merely subsonic at 260 meters per second.
They were in a completely different league from attacks like Misaka Mikoto's Railgun, which could reach speeds of dozens of Mach.
But to Accelerator, these attacks could still be fatal. He had to defend against them with reflection and Vector Manipulation.
Under normal circumstances, tens of thousands of such Electromagnetic Bullets would have been nothing to him. He could block them effortlessly.
But now, he could not stop coughing and even found it difficult to breathe. His combat