Summary
Used by most if not all characters that make upNaruto’smain cast, the Summoning Jutsu is one of themost memorable techniques in the seriesand many of the most prominent shinobi within this world have equally memorable summons associated with them. In essence, the technique permits a user to instantly bring a specific animal or object to their location, based on a contract signed between them.
Some of the most well-known battles throughout both Part I and II ofNarutohave featured the Summoning Jutsu as part of their exchanges, with the Sannin’s Three Way Deadlock as well as Team 7’s own version having gone down as some of the most emphatic uses of the technique in the series.Naruto Uzumaki himself spent a great deal of timein Part I to learn the technique, prior to his eventual fight with Gaara during the Konoha Crush. But how exactly does this jutsu work?

What Is The Summoning Technique?
Permitting shinobi to instantly call on targets — usually animals — to their location to assist them in combat, the Summoning Jutsu is one of the most useful techniques in a shinobi’s arsenal. Although the underlying mechanics behind the jutsu have not been explained in full, the process to perform a Summoning Jutsu commences with a contract between the summoner andthe animal or species to be summoned.
The nature of the contract can varydepending on the animal being summonedas each species has its own unique version. After the contract has been made, the summoner has to make a blood offering to activate the technique. This is generally accomplished by biting one’s finger, but it is not uncommon for shinobi to use blood from wounds that they have already sustained in the heat of battle.

Subsequently, the summoner must press their fingers down on to the ground or any surface — sometimes even in midair — channeling chakra to call upon the animal they have made a contract with. When the jutsu is activated, a formula will spread out from the user’s fingers across the surface they have chosen. Even after a shinobi’s death, the contract remains valid, as those brought back to lifeby Kabuto’s Summoning: Impure World Reincarnationin the Fourth Shinobi World War were able to call upon their animal summons after being revived.
Interestingly, the Summoning Jutsu isalso classified as a form of Space-Time Ninjutsu, indicating that the objects being summoned are essentially teleported to the summoner. Hence, shinobi can also benefit from using the Reverse Summoning Technique, where the animal is the summoner and the shinobi acts as the target of the summoning, enabling them to travel large distances in no time. While animals brought to a location by the Summoning Jutsu will return to their place of origin if they are fatigued or incapacitated, shinobi who are transported to a place by the Reverse Summoning Technique can remain there almost indefinitely, unless summoned back to their original location.

Different Types Of Summons
Little has been explained about the type of contract made for each species, save for a few. The contract tosummon the toads of Mount Myobokuconsists of a scroll that the summoner signs their name on with their own blood and also marks their fingerprints. On the other hand, Orochimaru, who summoned snakes, had his contract tattooed on his arms, and he smudges blood across it whenever he activates his Summoning Jutsu.
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The amount of chakra determines the size of the summoned target, as smaller animalswill arrive if there is too little chakra suppliedwhereas multiple large animals can be called on if the amount of chakra infused is sufficient. If a pair of shinobi have made a contract with the same animal, they can pool in their chakra in case one or the other is fatigued. Finally, if a summoner has the blood of a deceased individual who had made a contract with an animal, they will be able to summon said animal if they use the blood they possess, but only after infusing their own chakra into the technique.
It is also possible to summon more than one species, as Sasuke was able to call on both snakes and hawks. Additionally, once summoned, the animal has little obligation to obey the summoner’s commands, with situations such as that of Manda, who often threatened to kill his summoners. There is one exception to the traditional limits of this technique for those who possess the Rinnegan. For such individuals, the normal constraints of the technique do not really apply as they have access to a variety of summons through the Animal Path, which do not require the creation of a contract. Furthermore, Rinnegan users can also summonthe Demonic Statue of the Outer Path, which is the husk of the Ten-Tails sealed centuries prior to the start of the story.
Into The World Of Derived Techniques
Beyond the basic Summoning Jutsu, there are a host of extended techniques which use it in combination with other jutsu, or add conditions to its activation which augment its scope. This includes the Amplification Summoning Technique, which attach a condition granting a special ability to the animal that has been summoned.Nagat as Pain used this jutsu with the Giant Multi-Headed Dogfrom his Rinnegan summon, allowing it to multiply on receiving damage.
Summoning can also be used for more evasive or direct offensive measures, as seen in how Orochimaru often summoned snakes from his arms or the ground to divert his opponents' attention. The target of a Summoning Jutsu need not be an animal, and can also be an inanimate object or even deceased souls,as in the case of the Summoning: Impure World Reincarnation. For instance, Tenten regularly used scrolls to seal away her vast arsenal of weaponry, and she used the Summoning Jutsu to retrieve them during a battle. Orochimaru has also used the technique to summon Rashomon gates to withstand incoming attacks, highlighting how versatile this jutsu is.