Fourth Shinobi World War

The is a conflict between the Allied Shinobi Forces and Akatsuki. Its beginning was declared by Madara Uchiha when the five Kage and the leader of the Land of Iron unanimously refused to surrender the Eight-Tailed Giant Ox and the Nine-Tailed Demon Fox for his Eye of the Moon Plan. Madara then stated that he would use the seven tailed beasts already captured by the Akatsuki in combating the ninja world. After this the Fifth Kazekage, the Fifth Mizukage, the Fourth Raikage, the Third Tsuchikage, and General Mifune agreed to form a Shinobi Alliance, pooling their resources against Madara. Later the daimyō of the Five Great Shinobi Countries and the Fifth Hokage joined the alliance while Kabuto Yakushi formed an alliance with Madara.

Preparations for War
Both sides began by gathering their strength and collecting information about the other side in preparation for the upcoming hostilities. Kisame gathered intelligence on Kumogakure's military strength and on Killer B while travelling with him everywhere hidden inside Samehada. The team of Anko Mitarashi tracks Kabuto Yakushi, which led them to Madara Uchiha's headquarters. Other Shinobi Alliance teams have fanned out to collect other information about Akatsuki and their hideouts.

Kabuto has formed an alliance with Madara, showcasing his use of the Summoning: Impure World Resurrection technique, increasing the forces of Akatsuki with the resurrection of deceased members of the organisation. The Five Kage have decided to hide the two remaining jinchūriki, Naruto and Killer B on an island in the Land of Lightning. Hiding Killer B and Naruto had the unintended result of allowing Naruto to learn to control the Nine-Tailed Demon Fox's chakra, much like the way Killer B has of the Eight-Tailed Giant Ox. Having been successful in his training, Naruto has exhibited increased speed and strength when utilising the controlled chakra of the Nine Tails but lacks the same finesse that Killer B had exhibited in utilising the Eight Tails', crashing into the wall and crushing rocks whenever he uses the Nine Tails chakra.

Despite being captured in the end and committing suicide to keep the information he held secret, Kisame was able to finish Akatsuki's preparations for the War by sending a summon shark with a scroll to his comrades, divulging the proximate location of the Turtle Island. With the battle between the two forces seems to be on the horizon, Madara had dispatched Kabuto to retrieve the Nine-Tails and Eight-Tails with the revived Deidara but was stopped by Ōnoki, Akatsuchi and Kurotsuchi who was going to reinforce the forces on the Island Turtle. But Kabuto still made it out with Yamato, further adding to the intelligence sources that Akatsuki has on the Shinobi Alliance and also intending on strengthening the Zetsu's with Yamato's powers.

Both the Allied Shinobi Forces and Akatsuki have amassed considerable forces for this war, 80,000 shinobi and samurai total make up the Alliance and 100,000 Zetsu clones and many warriors of note revived by Kabuto make up Madara's army.

Allied Shinobi Forces
The Allied Shinobi Forces created by the Five Great Nations and the Samurai of the Land of Iron consists of five main divisions, with Gaara of the Sand as the Regimental Commander. The 1st Division consists of mid-range fighters and is led by Darui. The 2nd Division is made up of close-range fighters and is led by Kitsuchi. The 3rd Division is under the command of Kakashi Hatake, and features both close- and mid-range fighters. The 4th Division contains only long-range fighters under the control of Gaara. Shikamaru is Gaara's right hand man and proxy commander of the Fourth Division as well. Finally, the 5th division was created for the purpose of special operations, and features ninjas with unique skills. Mifune is the leader of these special operatives. There are also four special divisions formed for the war. The Logistical Support and Medical Division led by Shizune comprises of medical ninja, the Surprise Attack Division led by Kankurō, has the task to ambush the enemy forces. The third is the Sensor Division with Ao as captain, and finally the Intelligence Division headed by Inoichi Yamanaka is intended to gather information and relay it to Gaara for strategy's sake.

Akatsuki
Akatsuki is composed of Madara Uchiha and Zetsu. Their primary fighting force is composed of 100,000 Zetsu clones created through a combination of the tailed beasts' chakra and Hashirama Senju's power. Madara plans to use Sasuke Uchiha once he has recovered from his Mangekyō Sharingan transplant. Kabuto Yakushi has also joined forces with Akatsuki, reviving a large number of once-famous powerful shinobi to supplement the Zetsu army.

Initial Deployment
Analysing their own and their enemy's location, they have decided that Akatsuki will send a small fraction of their army by sea from the Mountains' Graveyard (Akatsuki's hideout) to Kumogakure, and that most of the army will travel by land. This would require the army to move through both the Land of Frost and the Land of Hot Water. An immediate evacuation notice was sent to both countries, and they will most likely evacuate to the south, in the Land of Fire. The First Division, which is the mid-range battle division, is stationed in the northern part of the Land of Lightning, in order to prevent the Akatsuki from using the small gulf to infiltrate the area from Mountain's Grave. The Second Division, or short-range battle division, is on the border of the Land of Lightning and the Land of Frost, sealing a northerly path into the Land of Lightning. The Third Division, or the short- to mid-range battle division, was advancing fast through the middle of the Land of Frost, but was called into the northern part of the Land of Hot Springs to aid the Surprise Attack Division. The Fourth Division, the long-range battle division, is on the border of the Land of Lightning and the Land of Frost, sealing a southerly path into the Land of Lightning. Mifune's Fifth Division, the special battle division, is aligned in a large arc from the north part of the Land of Frost, through the middle of the border between the Land of Frost and the Land of Lightning, all the way to just south of the First Division, in order to aid any of the divisions that need immediate response, and to finish the seal on the Land of Frost and the Land of Lightning's border.

Secondary Deployment
As the confrontation develops, resulting in both the First and Fourth Divisions opposing two separate yet equally significant contingents of the enemy's forces, Shikaku Nara devises a strategy to better reflect the conflict's current developments. Confronted with two distinct groups, the decision is made not to individualize the targets and instead concentrate entirely on those facing Darui's First Division, by connecting their forces with those stationed within the Easterly end of Mifune's Fifth Division. The majority of Kitsuchi's Second Division will move simultaneously to this, proceeding along the ocean and sandwiching the enemy force in a pincer-manoeuvre, while the remainder attends to the adversaries that they are already battling.

Consequently, this will severely thin out the Second Division but as the Fifth Division fills in the gaps left behind by the Second Division, it will match that of the Fifth Division's formation, which then provides a solitary yet solid line of defence. As this occurs, Gaara's Fourth Division will make a slow retreat while moving into a sideways chevron formation, luring the enemy into following them. Eventually the top portion of this 'line' will break away and join the First Division, giving them yet further support.

Once the first targeted group of enemies is defeated, the joint forces of the First and supporting Fourth Division will switch to the remaining opposition at Gaara's Fourth Division, approaching from behind and decimating them in a single decisive strike. However; this preliminary plan relies upon the swift mobilization of the Second and Fifth Divisions, so as to best employ Kitsuchi's units experience in combating the current enemy, and the belief that the opposition will be unable to mount a full attack upon the retreating long-range battle division, due partially to the enemy's suspicion over why the Fourth Division would split and their inability to get in close.

As night falls, the Alliance takes the opportunity to centralize the Logistical Support and Medical Division behind their defences to attend to all the wounded shinobi. The compound is guarded by two Akimichi clan members at it's only entrance and the chakra of anyone entering the compound is verified and cross referenced with the Alliance's headquarters.

Akatsuki
Much less was initially known about the Akatsuki strategy, but it was made evident that their primary objective remained the acquisition of the surviving jinchūriki. From the small amount of information that had been divulged; Kabuto would maintain direct manipulation of the movements of the resurrected individuals until they had reached their appointed destinations, with the intention of eradicating their personalities when the actual conflict began to turn them into mindless implements of death, while still manipulating any emotional response they could potentially illicit to full advantage, in the hopes of inflicting further damage. During the course of this approach, a small Surprise Attack and Diversion Platoon (comprised of Sasori, Deidara, Chūkichi and Shin) would attack from the air, utilising bombs and traps to disperse the enemy. However, realising that the movement of their entire army in such a large and apparent fashion would be far too conspicuous, the decision was instead undertaken to dislocate the 100,000 Zetsu clones beneath the ground, in order to thoroughly conceal the approach of the main contingent of their forces. Though a large amount of these clones were eventually unearthed, thousands more were able to proceed unobstructed underground to their respective battlegrounds, due in part to the diversionary tatics made possible by the addition of Kabuto's resurrected shinobi.

Concurrent to the developing conflict, the black half of Zetsu would utilise the resulting turmoil in order to infiltrate the daimyō's safe house as per Madara's orders, with the sole intention of using these valued captives as bargaining chips to draw out the jinchūriki. However, with the jinchūriki's decision to expose themselves and take direct action before this assignments completion, it was deemed unnecessary and so Zetsu's role was altered to instead engage with the daimyō's guards, ensuring their continued separation from the remainder of the Allied Shinobi Forces.

As the confrontation progresses and night falls upon the first day, Madara's true intentions and the reasons behind his confidence in his original strategy, which didn't account for Kabuto's inclusion or contributions, are revealed. Aware that the darkened conditions would effectively force the two opposing sides into a staring contest, as the Allied Shinobi Forces tighten their defences and become completely reliant upon their sensor shinobi in order to remain vigilant, Madara's scheme takes advantage of this over dependency by utilising the Zetsu clones' Substitute Technique in conjunction with the chakra obtained during the previous battles. By covertly placing these transformed Zetsu amongst the injured and scattered troops of the enemy, once they have assumed the forms of other Allied Shinobi, they could then proceed to indiscriminately assassinate any isolated individuals, while remaining undetected due to the Zetsu's possession of charka identical to that of members of the Allied Shinobi Forces. This resulted in causing chaos and dissension within the ranks of the enemy, as they began to suspect one other of committing these deeds without any definitive way to distinguish friend from foe, while also minimising the causalities suffered by the Akatsuki forces in the process.

Prelude Battles
As both sides prepared for the war, Akatsuki continued its standard methods of capturing the jinchūriki.

Capturing the Eight-Tails

 * Location: Sabu's Home
 * Combatants
 * Akatsuki: Kisame Hoshigaki, Zetsu
 * Enka/Cloud Ninja: Killer B, Sabu, Ponta, A, C, Darui
 * Outcome: Kisame able to infiltrate the Allied Forces. Akatsuki strategic victory, Allied Shinobi Forces tactical victory.

After tricking Taka into believing they had captured him, Killer B sought out the enka ninja Sabu to learn from him. Kisame Hoshigaki tracked him down with Samehada and the battle ensued. When the Fourth Raikage and his two bodyguards Darui and C arrived, Kisame was thought to have been killed. This was, however, a unique clone created by Zetsu and the real Kisame was hidden inside Samehada, which Killer B had claimed, to gather information on what the Allied Forces were going to do with the shinobi.

Battle on the Island Turtle

 * Location: Island Turtle
 * Combatants
 * Akatsuki: Kisame Hoshigaki
 * Allied Shinobi Forces: Aoba Yamashiro, Killer B, Might Guy, Motoi, Naruto Uzumaki, Yamato
 * Outcome: Kisame killed, Akatsuki finding the location of the jinchūriki, and gaining intelligence on the movements of the Allied Shinobi Forces. Akatsuki strategic victory, Allied Shinobi Forces tactical victory.

By hiding in Samehada, Kisame was able to not only gather information on the Allied Forces base of operations but the location of the jinchūriki as well. Travelling with Bee to the Island Turtle he remained unnoticed by everyone until Naruto's new power allowed him to sense Kisame in the sword. As Kisame fled, he was encountered by his old foe Might Guy and the two squared off in a final battle. Using his Daytime Tiger, Guy managed to capture Kisame but before he could reveal any information he killed himself with a shark summon.

With Kisame dead, the Allied Forces attempted to figure out what Kisame had managed to learn about them through the scroll he left behind. When the scroll opened, the trap activated, trapping everyone in a Water Prison Technique and summoning another shark to take the information scroll back to Madara.

Battle for the Rinnegan

 * Location: Amegakure
 * Combatants
 * Akatsuki: Madara Uchiha
 * Amegakure: Konan
 * Outcome: Madara obtains the Rinnegan, Amegakure loses its village head, Konan. Akatsuki victory.

Madara Uchiha confronted Konan within Amegakure in order to obtain the Rinnegan from Nagato's corpse. Having prepared to fight Madara, Konan had integrated over 600 billion exploding tags into her paper jutsu, knowing that Madara can only stay intangible for five minutes and set off enough explosions to last ten minutes. With her chakra depleted, Madara revealed that he survived the explosions using the power of Izanagi sacrificing his left Sharingan. He then used a genjutsu to get Nagato's location from her, killing her in the process, Madara claimed Nagato's body and took the Rinnegan for his own.

Second Battle on the Island Turtle

 * Location: Island Turtle
 * Combatants
 * Akatsuki: Deidara, Kabuto Yakushi, Manda II
 * Allied Shinobi Forces: Akatsuchi, Aoba Yamashiro, Kurotsuchi, Motoi, Ōnoki, Yamato
 * Outcome: Yamato captured. Akatsuki victory.

With the jinchūriki's location known, Kabuto volunteered to capture the jinchūriki. Kabuto chose the resurrected Deidara to accompany him and to set out to find the island by air. The Third Tsuchikage and his guards, being notified that the island turtle's location has been compromised, flew to the island to defend it from potential attack. The two parties intercepted each other en route and the Tsuchikage and Akatsuchi opted to fight Deidara while Kurotsuchi pursed Kabuto to the turtle. Deidara, Akatsuchi, and Ōnoki's battle ended in a stalemate.

The island turtle, which had moved from the previous location, was quickly found by Manda II. The giant serpent flipped the entire turtle over stopping its movement. Yamato, Motoi and Aoba left the inner part of the turtle shell and encountered Kabuto just as he and Kurotsuchi arrived. Kabuto avoided their combined efforts by revealing that he had turned his body into a giant white snake, similar to Orochimaru. Figuring that the jinchūriki were too protected to be captured alone, he instead captured Yamato, the last living user of the First Hokage's Wood Release and returned to Mountains' Graveyard.

Battle of the Surprise Attack Divisions

 * Location: Land of Hot Water
 * Combatants
 * Akatsuki: Surprise Attack and Diversion Platoon
 * Allied Shinobi Forces: Surprise Attack Division, Infiltration and Reconnaissance Party (third team, except Anko)
 * Outcome: Deidara is captured. Shin and Sasori return to the afterlife. Chūkichi flees. Anko Mitarashi is imprisoned. Muta Aburame is killed. Allied Shinobi Forces victory.

Both Surprise Attack squads meet coincidentally in the Land of Hot Water, and they engage in battle. Akatsuki makes the first move, but the Allied Shinobi Force's numbers and strategy of luring Akatsuki into their terrain give them the upper hand. The Allies were able to use their emotions to put them at their highest capacity, including a calm Omoi, a furious Sai, and a determined Kankurō.

Allied Force's Ambush

 * Location: Land of Hot Water
 * Combatants
 * Akatsuki: Haku, Pakura, Gari, the previous Seven Ninja Swordsmen of the Mist
 * Allied Shinobi Forces: Part of the Surprise Attack Division, Third Division
 * Outcome: Ongoing. Tajiki and dozens of Allied Shinobi killed or wounded. Zabuza and Haku immobilized.

The Surprise Attack Division launched an ambush on the Akatsuki shinobi, which easily survived the attack. They then notified the Third Division with a flare, who quickly arrived. Zabuza Momochi then pleaded with Kakashi Hatake to kill them, then Kabuto Yakushi's jutsu forced the battle to begin. Zabuza concealed the Akatsuki's movements with his Hidden Mist Technique. Pakura used Scorch Release: Extremely Steaming Murder to kill at least two ninja, and Tajiki was killed by Gari with Explosion Release: Landmine Fist. Sakura Haruno, being a medical ninja, helped heal the injured. Pakura and Gari then summoned the rest of the previous Seven Ninja Swordsmen of the Mist. The new swordsmen then attacked, using their superior swordsmanship to kill at least a dozen more allied shinobi. Kakashi developed a plan involving Ensui Nara, Santa Yamanaka and Maki to seal Zabuza and lift the mist covering the battlefield. However, Haku once more saved Zabuza, holding Kakashi in place, which Zabuza tried to exploit by attempting to slash through both of them. Kakashi was slashed yet survived and immediately countered, allowing Maki to immobilize the recovering Haku and Zabuza, stopping the Hidden Mist Technique. Later Kakashi's division seemed to have retreated into the forests, the battle seems to be ongoing.

Battle in the Land of Frost

 * Location: Border of the Land of Frost and the Land of Lightning
 * Combatants
 * Akatsuki: Around 20,000 clones of the White Zetsu Army
 * Allied Shinobi Forces: Second Division, westerly section of the Fifth Division
 * Outcome: Tactical withdrawal of the Allied Shinobi Forces to aid the First Division. Eventual Allied Shinobi Forces victory

Kitsuchi and Kurotsuchi used Earth Release: Opening Earth Rising Excavation to unearth the moving Zetsu army, and then the divisions immediately attacked. The opening shots seemed to have destroyed a significant quantity of the Zetsu clones before they had a chance to mount any form of counter-attack. However, as a seemingly unending number of durable clones continued to emerge, the conflict quickly descended into one of attrition, tiring much of the Allied Shinobi Forces and allowing thousands of the clones to proceed without hindrance underground. Part of the Second Division went to aid Darui's First Division. Eventually, the remaining troops apparently defeated the rest of the White Zetsu Army in the area and were seen resting after the battle.

First Battle on the Land of Lightning's Coast

 * Location: North-western coast of the Land of Lightning
 * Combatants
 * Akatsuki: Thousands of the White Zetsu Army, Asuma Sarutobi, Hizashi Hyūga, Dan Katō, Kakuzu, Kinkaku, Ginkaku
 * Allied Shinobi Forces: First Division, parts of the Second Division, Fourth Division and the eastern tail of the Fifth Division
 * Outcome: Atsui, Samui, and Ginkaku sealed within Benihisago. Kinkaku sealed in Kohaku no Jōhei. Asuma Sarutobi sealed. All White Zetsu clones involved defeated. Portion of the First Division killed. Dan Katō restrained with Four Violet Flames Battle Encampment. Kakuzu and Hizashi Hyūga contained by Chōji Akimichi. Allied Shinobi Forces victory.

Darui and his division awaited the section of the White Zetsu Army that passed under the Second Division, making preparations to fight them and the resurrected shinobi as they came ashore. The Gold and Silver Brothers then began their battle with Darui, who is supported by Samui and her brother Atsui, both of whom are quickly incapacitated. During the confrontation, countless White Zetsu clones continue to be destroyed in the immediate vicinity. A fortunate Darui manages to steal the Benihisago and the Shichiseiken, before sealing Ginkaku and causing Kinkaku to perform a tailed beast transformation in response, who then proceeded to devastate much of the First Division in an attempt to kill his brother's captor. Parts of the Second, Fourth, and Fifth divisions arrived to help the overwhelmed First, with the Kohaku no Jōhei being sent to the battlefield by Mabui around the same time. This allowed Darui, acting in conjunction with Ino, Shikamaru, and Chōji to seal Kinkaku within the pot. With Kinkaku's imprisonment, the battle began anew with Kakuzu obtaining the fifth heart needed to use his Earth Grudge Fear. After sending the four masks out into the conflict, Izumo and Kotetsu managed to catch him off guard and slice through his body, pinning his arms in order to prevent him from regenerating. Darui is then ordered to help the pair while Ino, Shikamaru, and Chōji are sent to deal with the resurrected Asuma, who was slaughtering a considerable amount of shinobi. Chōza and Dan continue their battle, with preparations being made in order to avoid the latter's use of his Spirit Transformation Technique. Team 10 continues there battle with Asuma, after using a calorie-enhanced chakra punch Chōji defeats Asuma; later he expands his wings further and claims that he will end this battle himself. Later, the battle is seemingly over, with Dan restrained in the Four Violet Flames Battle Encampment, Kakuzu and Hizashi Hyūga defeated by the Alliance. Tenten overstrains herself from using the Bashōsen and receives medical attention.

Battle in the Land of Hot Water

 * Location: Land of Hot Water
 * Combatants
 * Akatsuki: Hanzō, Chiyo, Kimimaro, Chūkichi, Ibuse
 * Allied Shinobi Forces: Part of the Surprise Attack Division, Mifune, samurai and at least one shinobi of the Fifth Division
 * Outcome: Ongoing. Deidara remains captured. Ibuse killed. Hanzō sealed, Kankurō's portion of the Surprise Attack Division paralysed.

Attempting to retrieve the captured Deidara, a portion of Kankurō's division encounters an elite Akatsuki unit and immediately tries to retreat to escape the superior opposition. In response, they are instantly paralysed by Hanzō's summoned Ibuse but Mifune manages to intercept Hanzō's fatal attack, before requesting a duel with the deceased shinobi. Samurai then arrive to back up Mifune and decide to take the poisoned Surprise Attack Division to the Logistical Support and Medical Division. Mifune then faces Hanzō alone, while the samurai fight Kimimaro. Mifune cuts Ibuse's head open, and convinces Hanzō against fighting. Hanzō then performs seppuku, causing his own poison to paralyse him. The Surprise Attack Division was given an antidote, and recovered enough to seal Hanzō.

Second Battle on the Land of Lightning Coast

 * Location: North-western coast of the Land of Lightning
 * Combatants
 * Akatsuki: Madara Uchiha, the Demonic Statue of the Outer Path
 * Allied Shinobi Forces: First Division, parts of the Second Division, Fourth Division and the eastern tail of the Fifth Division
 * Outcome: Dan Katō freed, Kakuzu sealed, hundreds of Allied Shinobi dead in Demonic Statue of the Outer Path rampage, Madara Uchiha retrieves the Benihisago and Kohaku no Jōhei for containing the Gold and Silver Brothers. Akatsuki victory.

Almost immediately after all the participating members of the White Zetsu Army were defeated, as well as Hizashi Hyūga, Kakuzu, and Dan Katō were all restrained, Madara Uchiha initiated a new battle right off the coast by summoning the Demonic Statue of the Outer Path.

At the end of the first day of battle, both the Allied Shinobi Forces and Akatsuki received massive casualties, effectively halving both their battle forces. The 80,000 strong Allied Shinobi Forces were brought down to 40,000, and the 100,000 strong White Zetsu Army was brought down to 50,000, on top of the already sealed resurrected shinobi.

Trivia

 * Itachi Uchiha prevented an earlier potential outbreak of a Fourth Ninja War by carrying out the Uchiha clan massacre.
 * A Fourth Ninja War was also declared by Hiruko in the third Naruto Shippūden Movie, and would have pushed through if not for the efforts of the Konoha 11.