In the Battle of New York, Tony didn't use this armour because of its main weakness! It was only useful for close combat! Tony didn't need a Vibranium coated armour for ranged combat as he could always dodge anything. Plus, he still couldn't find a better use for Adamantium Alloy except for a sharp weapon!
Because of this weakness too, Tony has been keeping this armour hidden until now since he believed that now was the right time to use it! Killian was using a power that derived from heat, so the use of Vibranium coated armour was a must as the Vibranium would absorb the energy that was produced from heat and transformed it into raw energy!
And as Killian also used close combat, he wouldn't have any chance to block Tony's attack using his knife made from Adamantium! Even if Killian could heal himself numerous amounts of time, there would be a limit to that ability! There was no way that a human would be thatr invincible. Maybe if Tony cut Killian's head off, Killian would finally dead!
But Tony wasn't in a rush. It seemed like he wanted to vent off some of his frustration to Killian!
Knowing that he had no easy means to win, Killian immediately retreated while Tony was chasing after him, reversing the cat and mouse game that they were playing from the start! Tony would frequently catch up to Killian and chopped some Killian's limbs, but Tony wouldn't end Killian's life just yet!
"Blow him up!" Killian shouted as he became desperate to get away from Tony. He didn't understand why Tony suddenly became so strong! The people injected by the Extremist Virus knew that this was their end game, so they were already prepared to die! A bunch of Killian's followers quickly hugged Tony and suddenly exploded, creating a sea of fire that would instantly kill any normal person!
But unfortunately for Killian, Tony had already prepared for this! While Killian thought that Tony was finally dead, a flash of twirling light suddenly shot towards Killian at great speed! This was the Adamantium knife that Tony used earlier! It successfully penetrated Killian's chest in one go, pinning him to the wall! Then Tony emerged from the raging fire as if nothing happened.
Killian was surprised that the explosion earlier had no effect on Tony, and so he tried to escape once more! He tried to melt the knife on his chest to get away, but no matter how hard he tried, the knife wasn't affected!
"Fuck this!" Killian said as he slid off the knife to the side, cutting half of his body! But the regenerative power from the Extremist Virus immediately healed his body once more. But, because he took too long to escape, Tony was already closing in and held him to the ground.
"You can't kill me, Stark! If I die, Pepper will also die with me!" Killian said as he laughed hysterically.
"What did you just say? What have you done to Pepper?" Tony asked as he shook Killian's body rudely.
"Did you honestly think that I only want to kidnap the President? I've already dispatched some men to capture Pepper while you were busy saving Mr. President earlier!" Killian said as he laughed.
"Bastard!" Tony said as he pounded Killian's face in frustration.
"Kill me, Stark! See if I lied!" Killian said while still laughing hysterically like a maniac. Tony raised his fist once again but failed to land his punch as there was a chance that Killian was telling the truth! But suddenly, a familiar voice was heard.
"Don't listen to him, Stark! Pepper is safe at my place!" Dio said casually as he walked towards Stark and Killian.
"Dio? What? Why are you here? and by the way, what is that shirt you are wearing?" Tony asked curiously. The shirt that Tony mentioned was none other than the [White Album] armour, it may look bizarre, but it worked!
"Make it quick, Stark! I still have a dinner appointment later!" Dio said anxiously as Tony was talking too much.
"Impossible! There is no way you can kill an extremist so easily!" Killian said to Dio as he gritted his teeth furiously.
"Listen to this guy, Dio. He has been spending too much on his small pond that he doesn't know that there are still many people more powerful than him!" Tony said sarcastically. "Did you know why I made this armour, Killian? That is because none of my armour would fare against this guy! He could destroy my armour completely in mere seconds, I tell you! now, I need to apologize to Pepper after this!" Tony said to Killian sarcastically.
"No, you can't kill me, Tony! He is lying!" Killian said desperately, but it didn't work as Tony immediately slashed his neck and lopped Killian's head off into the sea! The extremist virus sure could regenerate missing limb, but as the head was removed, it could no longer work!
"Is Pepper really safe?" Tony asked Dio hopefully.
"Well, she was worried for sure! She was lucky you know, if she didn't come to my Restaurant earlier, she might have been captured by the terrorist!" Dio said casually.
"Well, I owe you one then!" Tony said annoyedly.
"So, does that mean my debt is paid?" Dio asked as he smirked to Tony.