All according to plan.
As Light had expected, Near had replaced the pages of the fake notebook, unaware that it hadn't been the real thing. Near hadn't even tested the fake Note before replacing its pages. His self-righteous morality was now going to be his death. Near didn't deserve to be called L's successor, not when he wasn't willing to get his hands dirty to win. Light's victory was about to be a total one.
Light had been worried about Mello's abduction of Takada, but he had managed to deal with that situation himself, and it seemed Mikami had done his part and not made any unnecessary movements. Near was none the wiser about the real Death Note.
Light opened his mouth, about to ask Mikami if he was done writing the names, when Aizawa abruptly spoke.
"Near... you said that the one whose name isn't written must be Kira. And I agree, it would make sense. So, with that in mind, if your plan failed and we started to die... shouldn't we kill everyone here before the Note has taken effect on everyone?"
Light whipped around to face Aizawa, horrified. Near's face showed shock for a brief second, before settling back into one of quiet consideration. Matsuda was clearly appalled. "A-Aizawa-san, what are you saying?"
"If everyone but Kira is going to die, then shooting them will only shorten their lives by a few seconds at most. If everyone starts having a heart attack then Kira wins and walks away alive. But like this, even though we'd all still die, Kira will die as well!"
Light struggled to keep his outrage under control, while Near twirled a strand of hair introspectively. "...Yes, Mr. Aizawa. I think you're right. If one of us has a heart attack, then we should shoot Mikami immediately, since that'll be enough proof that he is X-Kira. After that, you may shoot me first to be safe, while the SPK shoots Yagami Light first." He paused. "Actually, if anyone dies first, it will definitely be me."
"W-wait a second Near! There has to be some other way!" Matsuda stammered.
Near snapped his fingers. "Rester! Gevanni! Apprehend Mikami! Use any force necessary."
Light watched horrified as Rester pried open the warehouse door and Gevanni shot Mikami in the leg. Mikami howled in pain. "God!" he cried. "God, I did what you asked! Why is this happening?!"
Near had been watching with mild interest. "Gevanni, bring me the Note, if you'd please." Gevanni picked up the Note and moved towards him, while Rester kept Mikami pinned down, gun to head. Just as Gevanni reached him, though, Near's eyes widened, and he clutched at his chest. In spite of his rising panic, Light couldn't help but grin at what happened next. "Sh-shit," Near murmured, and toppled over. His eyes slowly closed.
"Near!" Rester shouted. He immediately collected himself and blew Mikami's brains out, just before his heart attack struck him as well. Gevanni and Lidner acted quickly, both shooting to kill Light. But Light was already in motion. Lidner's shot clipped him in the shoulder, while Gevanni's shot caught him in the side. Light fell and skidded on the ground, crying out in pain. Gevanni and Lidner both succumbed before either could fire off another shot. Mogi stared with horror at the scene unfolding before him. Only the task force members were still alive. "But that means... it was one of us the whole time..." Then he too, collapsed.
Ide moved to shoot Light, but Matsuda moved into his line of fire. "Matsuda, what are you doing?!" Ide shouted.
"Ide, no! We can't kill each other like this!" Ide didn't get a chance to retort though. He gritted his teeth in pain and fell over.
Aizawa's attention had been diverted by Matsuda, but he knew what had to be done. He took careful aim, knowing he only had seconds to kill Light. "A-Aizawa! Wait! You can't!" Matsuda shouted. Aizawa squeezed the trigger.
But Matsuda was faster. The crack gunman blew a hole in Aizawa's hand before he could shoot. The gun went flying, and Aizawa dropped to his knees, clutching his hand in pain. He felt the telltale painful throb in his heart. "Matsuda... you idiot..." he murmured through gritted teeth. Then he too died.
It was only then that Matsuda understood. Or, rather, it was only then that he stopped denying what he had already known. He aimed at Light and tried to squeeze the trigger. But he couldn't do it. Trembling, with tears pouring out his eyes, he asked the one question racing through his mind. "Why, Light? ...Why?" His heart throbbed, and he slumped down. Light had made it back onto his feet by this point. He was shaking from shock and pain. Matsuda crawled over and grabbed Light's leg, clutching at it feebly. Light glowered back down in cold contempt.
"Wh-what about... your... father?" Matsuda wheezed, then breathed no more.
Silence filled the warehouse. Light felt that he should have laughed then, long and hard. But he couldn't, for some reason. This victory felt... hollow.
"Kukukukuku," Ryuk chuckled. "Well, that was quite interesting. So now what, Light?"
Light was silent for some time. "I'm going to make a new world now Ryuk," he finally said. "I'll show you all sorts of interesting things." But his words sounded empty, and even the Shinigami could feel it.