Landing at the entrance of the Root, Kakashi crouched to examine the two dead Root guards at the entrance, with two precise slash marks along their jugulars. Not far from the bodies was Tobirama's blue armor, and one Root Anbu was missing a mask and their cloak.
'I see.'
Kakashi let a small smirk tug at his face mask before raising his headband. He removed what was left of his tattered flack jacket and donned the blank mask and plain cloak of the Root, pulling the hood over his noticeable hair before entering the base, memories of the base guiding his movement through the dark.
Passing by the many Root operatives, Kakashi scaled the walls and landed silently overlooking a small skirmish that was about to end.
"What is the meaning of this?"
Torune Aburame asked, swiping his blade at the Root member who shouldn't be anywhere near Danzo's office.
Tobirama didn't bother replying, ducking under the blade and palm striking him on the chest. A moment later, blood began to seep out of Torune's orifices, ears, eyes, nose, and mouth.
"W-what d-did you just do?"
Torune fell to his knees, his body protesting his stubbornness to stay up.
"I used the water in your body as a bomb, but it's a failed jutsu that I was never able to master. The result I wanted from the technique was the instant death of my enemies, but the control and chakra needed for that isn't worth it."
Tobirama replied before walking away, leaving the man to fall and bleed out.
'The principle of genjutsu applied to ninjutsu and biology, a scary technique.'
Kakashi followed along from above as Tobirama strode into Danzo's office as if he owned the place.
Danzo glanced up from behind his desk, glaring with his one eye at the 'Root' anbu who dared barge in without a hint of respect, his anger rising as he noticed the anbu wasn't even kneeling as is expected of a subordinate.
"What is the meaning of this? Where is Torune?"
"He asked the same thing as well."
Tobirama replied, reaching up to slide the mask off his face and toss it to the ground.
"Sensei?!"
Danzo was stunned, but his surprise didn't last long, silently giving way to an internal fear of the man in front of him. Danzo just hoped this man in front of him was someone under transformation.
"Tell me, Danzo, why can I sense my elder brother's chakra and several Uchiha eyes in that arm and covered eye?"
Tobirama got right to the point of it, not beating around the bush, internally rolling his eyes when he could feel Danzo's chakra surging.
Kicking his desk towards Tobirama, Danzo weaved through a series of hand seals.
'Wind Style: Vaccum Great Sphere'
Tobirama, having felt and expected the attack, weaved through the wind attacks and splintered wood, looking to Danzo just as he removed the seals and gauntlet on his arm, revealing the pale arm with Sharingan embedded in it.
"I had sensed you were dark, but I could've never expected this, Danzo."
"Don't lecture me, Sensei. It should have been me you chose for Hokage, not Hiruzen. Under Hiruzen, this village has become the laughingstock of the elemental nations. The Sand and the newly formed Sound village invaded us, and the Cloud blackmailed us with the Hyuga incident. This is all because you made the wrong choice."
Tobirama allowed his former student to rant, standing there with his arms crossed like a disappointed father.
"Utterly foolish. You're under the impression that I picked Saru over you because he happened to raise his hand and you didn't, correct?"
Tobirama watched the emotion flash behind Danzo's cold eye.
"I had every intention of making Saru the Third Hokage after that mission, even before learning about the ambush. It was time for the new generation to take over and lead; I was 65, ready to pass the position to Saru. Even if you'd have raised your hand first that day, the position of Hokage wouldn't have been yours."
Danzo roared and slammed his hand into the ground after a series of hand seals.
"Summoning jutsu: Baku!"
A large plume of smoke enveloped the room before a gigantic elephantine chimera appeared, squished in the room, but already opening its mouth and sucking in, pulling everything in its path.
Tobirama would have rolled his eyes if it wasn't beneath him to do so, a steady flow of chakra keeping him steady on the ground.
'Never thought I'd use the same technique in one day, that Kakashi brat will have to deal with the Root after I use it.'
Reaching into his chest, Tobirama plucked out a couple of handfuls of exploding tags and tossed them towards the elephant.
Danzo's eyes widened, unable to react in time as Baku was pulling everything in too fast, caught up in the explosion with his summons.
Tobirama glared as Danzo disappeared.
"Izanagi."
Danzo reappeared a few meters away, one sharingan eye closing on his arm.
"Yes, you would know this technique well."
Danzo replied sarcastically, a kunai sliding down his right sleeve and into his hand before lunging at Tobirama.
A single seal was what Danzo saw before a water dragon slammed into his chest and sent him flying into the back wall of his office, neck snapping violently.
This time, Tobirama knew what he was looking for: a marked kunai already heading where Danzo would re-appear.
Danzo tilted his head to the left on reflex, only realizing his mistake when the kunai had flown past him, but by then that same kunai was embedded hilt deep into the back of his ribs. Danzo faded away once more, wondering where his anbu were, unaware that they were being assassinated before they even reached his office door.
When he reappeared, Danzo unleashed a flurry of wind jutsu that cut through his office like a tornado, rage in his eye at the loss of Sharingan.
Tobirama stayed, jumping, side-stepping, and dodging jutsu as he finished his own.
'Fire style: Great Fireball Jutsu.'
The twenty-foot-wide fireball swept into and grew larger as the wind jutsu from Danzo fanned the flame, Danzo not able to finish his defensive jutsu in time before the flames engulfed him.
Appearing again, Danzo cooled his emotions, annoyed that he couldn't do anything about his sensei. Danzo was aware that he'd need fuinjutsu to seal Tobirama, but he didn't exactly have the resources on hand to deal with him. The best chance Danzo thought he had was to stall and get into a repetitive fight, hoping his anbu would show up or that Hiruzen would surprise him and save him from their sensei's wrath.
Tobirama observed the wind chakra gathering on Danzo's kunai, doing the same with his own as they closed the distance and began to clash blades, the screeching sound of chakra on chakra louder than metal alone could achieve, but one thing became apparent in their exchange: Tobirama held the advantage in close range as well.
Hooking Danzo's overextending right arm under his right arm, Tobirama slammed his chakra-enhanced left palm into Danzo's shoulder, popping his arm out of place.
Danzo screamed in pain, unaware of the two hand seals Tobirama had formed.
'Water style: Severing Wave.'
The compressed water cut through Danzo's neck like butter, removing his head from his shoulders.
After his seventh death, Danzo began attempting to flee, but turning your back on someone with flying raijin.
Appearing beside the fleeing Danzo, Tobirama slapped an exploding tag on his neck.
*Boom
Reappearing, Danzo looked to his right shoulder and noticed the Flying Raijin mark on him from his fifth death.
"You finally notice it. Yes, I could have ended this much sooner, but I wanted you to realize how hopeless your situation is. You know what it means to be marked by my flying raijin, you're done, Danzo, I've merely allowed you to live a bit longer."
"Why! What have I done to deserve death at the hands of my own sensei?!"
Danzo exploded, unable to rein in his emotions any longer, now that death loomed over and chilled him to the core.
"Don't act as if you're innocent! I'm no fool, Danzo! You stand here with my brother's DNA on your arm, along with the eyes of a dead clan! What have you done? NO, the question is What HAVEN'T you done?"
"Everything I have done has been in service to the village!"
Tobirama's chakra flared, glowing with an intense outline, before he was beside Danzo, right hand clenched around Danzo's neck as he lifted him up.
"You spout such righteous words, but do you truly believe in the things you claim? No, you're aware of the irony in them. You who have served the village have only seen its steady decline. Saru isn't perfect, but you're far worse, Danzo."
Tobirama replied before snapping his neck and tossing the body aside.
Danzo appeared for his last time, backing up into the remnants of his office wall away from Tobirama, the door to his office to his right, but Danzo knew he couldn't get away from his sensei.
"S-Sensei, please, let me go… I'll leave, never show my face in the Land of Fire again, I swear."
Tobirama gazed down at his hunched student with disgust, pity, and anger at him and himself for not seeing the true extent of the darkness Danzo held within, the last of the Root operatives' lives flickering to his keen senses.
"Fine, you can leave."
Danzo had a bit of life return to his eyes.
"Thank you, sensei."
Danzo ran out of his office, a sense of relief and joy that he was going to live and potentially become Hokage after Tobirama decided to move on.
*Squelch
"Agahh!"
Danzo robotically looked down to see a purple lightning-coated fist through his chest. Looking back, Danzo gazed at the blood-covered blank mast of a Root anbu.
Kakashi removed the mask with his other hand and eye-smiled at the older man, as if he didn't just punch a hole through him.
"Don't be mad at your sensei, he let you go, but he said nothing about anyone else finishing the job, nee?"
"Ka-Kashi-"
Danzo gritted out
"Hold that thought."
Kakashi's deft fingers slipped past Danzo's bandages and ripped out the eye of Shisui, not wanting the fool to use it as another life.
Kakashi ignored the shout of pain and violently ripped his arm free, letting Danzo fall to the ground.
Wheezing and slowly dying, Danzo reached for his robe, determined for one final move.
Kakashi examined the eye in his hand, smirking at Danzo's actions and speaking up in a teasing tone.
"Reverse Four Symbols Sealing."
Danzo's hand stilled on his shirt.
"H-how long ha-ve you."
Kakashi tilted his head with a casual shrug.
"When haven't I?"
Danzo didn't have time to understand the hidden implications as Kakashi pointed his index and middle fingers at him and shot him between the eyes with a tiny ball of compressed lightning.
Kakashi heard the soft chime once more, but ignored it for now, looking over to Tobirama.
"Want to see how twisted your former student has truly become?"
"Not particularly, but I feel that it would be wrong of me not to."
Tobirama sighed and followed Kakashi through the Root facility, ignoring the dead anbu that lay around the ground.
- Chapter End -
Hope you all enjoyed the chapter; it was never going to be great or anything. Danzo likely only had the Reverse Four Symbols Sealing, and I don't see Danzo's character as one who'd use it on a dead man, so his saving it and trying to use it on Kakashi makes much more sense, already being angry and annoyed with Kakashi for past actions and the more recent ones surrounding the chunin exams.