As Soren left with Luffy towards the Execution platform, Whitebeard decided to join the fight directly and came down off of his ship with his Bisento now ready for battle.
[All right! All who are prepared for possible death follow me!]: whitebeard
Whitebeard gave his crew some not so inspirational words of motivation then charged into the battle following after Soren and Luffy, he was then followed by all the pirate crews that came with him to rescue Ace. Soren and Luffy were coming up to the Execution platform when they were surrounded by thousands of Marine's, Soren was then back to back with Luffy while giving him some motivation.
[Do you remember our training?... If you can't beat these guys, then no dinner for you tonight]: soren
Soren said his words and Luffy thought it was the end of the world, and right before they could start taking out these soldiers Soren was hit by a fist of Lava and shot away from Luffy and the other Marine's.
[What the-...Hey you cheap bastard! How dare you take me away from my student when I am giving him motivation]: soren
Soren got up while wiping off some soot from his clothes, he then started facing the person who just attacked him, it was none other than Akainu. Akainu was surprised to see that Soren was able to stand there unharmed by his attack, even if it wasn't a full power attack Akainu still thought that it would have left a few burns.
[Neat tricks pirate, how did you pull it off?]: akainu
Soren was completely ignored and felt a little angry that Akainu would pass him off as someone who's words can be ignored, Soren then readied his weapons and aimed them towards Akainu, he then spoke with a cold tone.
[How about I cut a few limbs off then I can tell you right before I end your pitiful existence]: soren
Right after Soren said his promise he disappeared and reappeared in front of Akainu slicing off Akainu's left hand before disappearing and reappearing in his previous position covering his arm that had some burns on it.
[Your good kid but that's all, I could have killed you 6 times during your attack]: akainu
Soren was stunned to see that Akainu was able to attack him without him noticing, Soren then focused his Ki towards his arm and covered the burn to keep it from getting infected. Soren then started using his Observation Haki to the max and charged towards Akainu once again, every time Soren would make a swing of his swords Akainu would dodge with Kami-e (Paper Drawing) while giving off his own attack. Soren was at first angry the Akainu could avoid all of his attacks while making his own connect, no matter how hard Soren looked, even if he could see it coming 3 attacks into the future he still could not dodge them, but for some reason Soren was loving it. Every attack that hit him, ever move he did dodge, all the experience that tied into this fight, Soren was feeling growth, his Saiyan Bloodline was kicking in and forcefully making Soren stronger, his hands that every once in a while had itched like no tomorrow now were crying out in excitement.
'So this is what it means to be a Saiyan… I hope I don't become a masochist from this': soren
Soren was enjoying the fight so much that he forgot that he was even taking any hits, soon his body was covered in burn marks as blood was coming out of scabs that started to form from Soren's enhanced healing. Akainu was looking at this kid who looked as if he were seconds away from death's door and thought he was crazy, Soren started laughing as if this was the best joke he had ever heard in his life. Soren was enjoying the fight and didn't notice his Ki started to leak out and form nightmares for the weaker ones that were in a 200 meter radius of Akainu and Soren, everyone was in shock to see the beast that was Soren and how he had no form of self awareness for his well-being. Soren then decided to take it up a step and released his Susanoo, Soren was then surrounded by a pitch Black skeleton with Black smoke with hints of Teal smoke coming off of the skeleton.
[I wonder if you can take this… Amaterasu!]: soren
The skeleton then started firing off heaps of Black flames, all Akainu could think was.
[What in the Fuck is this kid!?]: akainu
Nobody who was spectating the fight between Akainu and Soren from the Marine's side could tell what Devil Fruit Soren had eaten, Soren displayed so many different powers that it was hard to tell what was happening. Akainu didn't try to dodge the Flames that shot at him because he was a Lava man, no fire could harm him, but he was wrong, once the fire hit him he started screaming in pain.
[AAHHHGGRRHH! Bastard! What are those flames!]: akainu
Soren who realized that Akainu was down for the count started to calm down his fighting spirit, the Susanoo then disappeared along with his MS and his eyes went back to the Black color they were. Soren then walked up to the fallen Akainu who was trying to put out the Amaterasu and crouched before him with his hands on his thighs, he then started to speak to Akainu in a calm voice.
[Those are the flames of a God, they can burn anything into ash, even reality… It was fun playing with you but our time ends here, Ace will be saved and you can die knowing that I, the teacher of the Son of Roger had killed you and everyone else here]: soren
When Akainu heard Soren he looked around to see what was happening and what side was winning only to see Garp and Sengoku fighting with Whitebeard, all the other pirates found their own target while some of the 7 warlords had traded sides and started fighting the Marine's and World Government, all the other Admirals and Vice Admirals were helping the higher ups in the World Government escape while Ace was no longer chained to the Execution platform but was escaping with the Rookie known as Monkey D. Luffy, with Akainu's final breath he used Shave and disappeared from his position and reappeared right behind Luffy and Ace while throwing all of his strength into his last punch sending a hole through Ace's chest while hitting Luffy as well.
[Son of a bitch!... I better act quickly to save Ace]: soren
Soren disappeared and reappeared behind Akainu while taking off his head with his Armament Haki infused sword, he then disappeared and reappeared next to Luffy who was hugging a dying Ace, Soren grabbed Luffy's shoulder and let Luffy grieve.
[Ace!... AACCCCEEE! WHAAAAHHH!]: luffy
Luffy unconsciously released a massive amount of King's Haki that hit everyone, Marine's and Pirates alike, everyone passed out except for those who had a stronger will. Jinbei then came next to both Soren and Luffy while assessing the situation, Soren then turned to Jinbei and spoke to him.
[Take Luffy and run from here, I will help Whitebeard clean up the rest]: soren
Jinbei nodded to Soren's words, he then grabbed the heartbroken and still sobbing Luffy then ran off to escape Marineford, Soren then knelt down and placed his hand over Ace's heart that happened to still have a bit of life left in it, Soren then took all of his remaining power and transformed it into Life Force Ki, Soren then took out a couple of Senzu beans while tossing them into Ace's mouth and forcing him to eat them, Soren then started forcing the Life essence into Ace's body, this started a rapid healing effect that started to close the hole in Ace's chest. After a couple minutes the hole was completely closed and Ace's heartbeat started coming back, soon after that it became normal but Ace stayed unconscious, Soren then looked around to see the battlefield, Garp was fighting Whitebeard to a draw, all the other pirates were picking up their fallen comrades due to Luffy's King's Haki, Soren saw all the Marines starting to flee leaving only some Vice Admirals left who were over by Akainu's body they had a Fruit in their hands which Soren guessed was Akainu's Devil Fruit. Soren then took another 2 Senzu Beans and ate them himself, he then started floating into the air and gathered a Black energy ball at the tip of his fingertip the size of a ping pong ball, he then flung it like he was flinging a booger off of his finger towards the group of 3 Vice Admirals. The shot hit the first guy taking off his head, the ball then changed direction and hit the other 2 who saw the first one die and tried to make a run with the Devil Fruit, the same scene happened with their heads flying off. The battle with Akainu had taken Soren to new heights after he ate those Senzu Beans, Soren was now 3… No, 4 times stronger than before, Soren flew down next to the Devil Fruit that dropped from the 2 deceased Vice Admirals' hands, and placed it into his storage, Soren then went back to Ace and put him on his shoulder and flew back to Soren's boat where Misha and Haku were waiting.
[Sorry Whitebeard, Luffy… I will give Ace back later, for now Luffy needs to train and Whitebeard needs to get his powers under control]: soren
Soren then broke the tiny bit of Ice that held onto Soren's boat and then started sailing to find a place to recover.
I hope this was a good insight into how a Saiyan perceives fighting, I read other Fan Fictions that have a Saiyan as MC and they don't portray it as well. Hell mine might still be missing stuff, also, I hope this was a good fight scene.