Eiji was bisected by Orochimaru's Kusanagi Sword, but he instantly starting to regenerate.
Since the start of the battle, Eiji was already "killed" many times, but always when Orochimaru tried to use fuinjutsu on him, Hiruzen interfered.
It was safe to say, that Eiji was completely trashed by Orochimaru.
He was only hanging on through his regeneration ability alone.
But unlike Orochimaru, Eiji has far less chakra and when he runs out of it, he won't be able to regenerate anymore.
Orochimaru was really targeting this weakness, focusing on Eiji, while the two Hokage fought against Hiruzen and Enma.
And since Eiji's and Hiruzen's plan was to seal the two Hokage, forcing Hiruzen to help Eiji out occasionally made it nearly impossible for him to achieve that.
'Shit if this goes on, forget about saving old man Hiruzen, I won't be able to save myself!' - Eiji tried something he hasn't used in a battle before.
He transformed into his giant snake form and used his huge body to attack Orochimaru and the two Hokage at the same time.
"Ha! To think you would try to use snake techniques against me! Laughable!" - Orochimaru summoned Rashomon to block the attack.
Eiji tried to move around it, but there was already Orochimaru waiting for him.
The Kusanagi Blade suddenly extended and with Eiji's huge snake body, he couldn't dodge and was hit.
Eiji started to transform back while also regenerating: 'This won't do...'
He glanced over to Hiruzen.
Despite Orochimaru focusing on him, Hiruzen, while still better than in the original timeline where he needed to fight Orochimaru as well, couldn't push his advantage and seal the two Hokage.
Winning a fight through sealing an opponent, was different than winning through killing the opponent.
'Sorry old man, but looks like I need to do this after all.' - Eiji dispersed another shadow clone, which gathered natural energy far away and entered Sage Mode.
"Hmph, you think Sage Mode will change anything?" - Orochimaru extended his blade again, but with Sage Mode, Eiji was able to sense it and dodge.
"Konoha-Wind Spirit Style: Summer wind of the sage!"
"YOU!" - Orochimaru saw that he was targeting the Sound Four, which were responsible for the barrier, and summoned two more Rashomon Gates.
Eiji's attack cut through the first two gates but was stopped at the last one.
The last Rashomon Gate reflected the damage back on Eiji, who was coughing blood while already starting to regenerate.
"Haa, looks like I need to use my strongest move after all..." - Eiji got into an iaistance again.
He stood there fully concentrating on accelerating chakra through his body.
But unlike the other techniques, where he only accelerates to a certain speed, he went beyond that.
It was truly dangerous and if he loses control of his chakra, he may end up as a human bomb.
Orochimaru sensed that this attack was going to be powerful and tried to stop him.
Unfortunately for him, Hiruzen appeared and defended him with a smile: "Aren't you interested in what he will show us too?"
'Let's add natural chakra as well...even though I have never done it before and it is even more dangerous, but as long as a finger remains, I can still regenerate...though with my chakra being almost empty this is probably the last time I can do this...'
He sensed that he was about to lose control, so despite wanting to accelerate further, he unwillingly unleashed it: "Konoha-Wind Spirit Style: Winter Storm of the Sage!"
The accelerated force went to his sword and when he drew it, the whole power was unleashed.
It was a brute technique, which spread the force in every direction since such a force was nearly impossible to control.
All the trees from Hashirama's jutsu were cut, and violent winds which cut with the power of blades rampaged through the battlefield, not caring if it's foes or allies.
'Shit! I can survive that easily, but the barrier will collapse at this point!' - Orochimaru saw that the problem wasn't the strength, but the huge area of effect.
"Yamata no Jutsu!" - Orochimaru used his strongest snake based technique just to save the Sound Four!
A giant serpent with eight heads and tails stood there and took all the damage for the Sound Four.
"Truly an impressive kenjutsu technique. Konoha's kenjutsu was never fully developed, but this youngster here achieved a kenjutusu level which is really of the highest level..." - Tobirama
"But this jutsu is quite problematic since it not only attack allies but the user as well." - Hashirama looked at Eiji, who was full of cuts and was covered fully in blood.
But despite that he smiled while regenerating a last time: 'Well, that's all I can do. Now it's all you, old man..."