The Outcast

Tartarus: 'Fallen son'

Izuku: "RRAH!!" swinging his hammer overhead to knock AFO through another wall...using the chains to keep him balanced in the narrow room...he then tries to go for the punch using an enhancement and then enlarging his fist...to punch him back 
AFO: "as always you act of your emotions alone...they bring out your true power...but it's not enough to defeat me..." seeing the dust rising in the room his hammer flew right out but he dodges it...as Izuku with the chains tried to attack but they were cut off immediately..
AFO: "sadly i cannot take them...for it could prove to be harmful...Ujiko is foolish" as Izuku then uses whitefrost to cover the room AFO now uses his own fire quirk...that came out as a ball of flames and let it soar through the room...even hitting him..but again..it does nothing to him 
Izuku: "KILLER!!" letting his full rage control him..the man who deceived him...forged him...taken his father...taken everything he holds dear...he lets it control him
AFO then grabs his hand to throw him aside...crashing into the wall he jumps right out and with his two back arms creates a ball of thermite then the white frost gathers on the other...AFO can see right through his trick...as he charges he waits for the opportunity...
Izuku: "DIE!!" but then to his surprise he detaches both arms to hit him with the thermite...right at his mask...which of course causes a good amount of damage to it..and then allowed the frost to come into contact with it...smacking him away the frost and thermite react and explode once more knocking both of them back 
AFO gets back up...and realized his mask was chipped...and something was itching at his lip...putting his hand up to it...he couldn't help but chuckle 
AFO: "all of that...for a drop of blood" now holding out his hands black tendrils pop out and they miss him but unaware of the apparent chain that hits the side of his mask...he turns to look at the detached arm from earlier still in tact...and it turns into frost and thermite exploding again...
AFO: "You really like your little fireworks...let me show you what true power looks like" as his muscles are coiling up...his arm enlarging as Izuku now grabbed his hammer and used the chains to launch himself forward...he lunges at AFO to try and hit him from the side...
AFO: "Excaliber" and then a huge gust of wind hits him directly...and he was blown away...the thermite flinged off his body and then multiple wounds opened up on him...and then the wind throws him up and then through the floor...hitting the ceiling and then fell back down to the level Izuku looking ahead nearly comatose from the massive amount of force 
AFO: "if you truly are the unkillable nightmare the people call you...you surely wouldn't have been knocked out this fast...you are just as pathetic as your father....the screams...the shouts and cowardly pleas for mercy instead of taking it like a 'legend' that those peasants call him...that people in their last moments...show you who they really are such as All mights mentor..she had shown me who she really is...one who no matter what...tries to protect something worthless..to Tomura begging for life....and then...the legendary hero who's ego is so high..he pleas like a rat trying to cling on to it's pathetic life...and then there's you...you show no fear...no cries...nothing...but hate and anger...to know that's how you truly are...i pity if you ever had kids" peering down at Izuku...who then went through that same damn vision. over and over again...
Izuku: 'and there we go again...the world just likes to toss us around and let us be forgotten...how wonderful' 
'and yet you keep on letting them...what about the vial?..we can finally show them what it truly feels like to fear?' 
Izuku: 'it's almost time...but i need more power...i want...more...power' 
'*sigh*...you need to channel more of your anger...otherwise..it won't happen' 
Izuku: 'i know' 
'remember why....remember' 
Izuku: "i...i remember!" 
AFO: "hmm?" 
Izuku: "GAH!!...GOD!!!" as he suddenly clenches his head...
AFO: "i'm rather surprised to see you get up so quickly...maybe you are stronger than i thought" but then something else happened...the room temperature felt like it was changing drastically from hot to cold...then he realized why...
AFO: "I see" even with the many quirks at his disposal..he cannot so much as interrupted or stop the process...as Izuku now started to get up...the ice and fire...has awakened