XY100

A Festival of Decisions! (Japanese: 忍者村決戦！ゲコガシラ対キリキザン！！ Decisive Battle in the Ninja Village! VS !!) is the 100th episode of the, and the 899th episode of the Pokémon anime. It first aired in Japan on December 10, 2015 and in the United States on April 2, 2016.

Blurb
While our heroes are visiting their friend Sanpei’s home in Ninja Village, Chief Hanzo is captured by a group of mysterious ninja! Their leader is Kagetomo, a gifted ninja who has decided that he should be chief in Hanzo’s place.

Sanpei and his brothers are determined to free their chief, and they confront Kagetomo and his forces head on, with the help of Ash, Serena, and Clemont. During the battle, Ash’s Frogadier evolves into an immensely powerful Greninja! The ninja force is defeated, and Kagetomo sees the error of his ways and decides to refocus on his training.

Ash and friends stay to enjoy the village festival, where Hanzo names Sanpei’s oldest brother, Ippei, as the next chief. After our heroes depart, the middle brother, Nihei, tells the others that he saw something in Ash’s Greninja that reminded him of the village’s ancient hero...

Plot
The episode begins with after they had captured  and Shinobu instead of their intended target. However, Shinobu performs the ninja body switch, allowing the two to readily escape Team Rocket's capture device. The then blast Team Rocket out of the village. Meanwhile, Ash and Sanpei begin to battle against Heidayu. Heidayu's dodges all attacks from, , and Sanpei's Greninja, and then attacks all three with. Despite Frogadier's frubbles and Greninja's, Bisharp remains unfazed and proceeds to attack them with. As they are about to lose against Heidayu, Saizo comes in to battle with his. Outnumbered, Heidayu retreats on a Skarmory, mentioning that he had bought enough time for Kagetomo. While Ash and Sanpei try to go after him, Saizo stops them, explaining that acting carelessly may cause them to lose their opportunity to save. At the village, the Skarmory fleet have also begun to retreat.

At Otori Mountain, Hanzo is captive with Kagetomo and his ninja corp. Hanzo tells Kagetomo to remove his mask as it was obvious from the ropes tying him that it was he who had captured him. At the village, Saizo tells everyone that it was Kagetomo and his henchmen who had kidnapped the chief. He explains to Ash and his friends that Kagetomo was a powerful ninja from the Ninja Village who was to be the next village chief. However, he had run away with Heidayu because he was denied the position of chief due to his thirst for power. Kagetomo had then formed a ninja force to capture Hanzo. Saizo had planned to stop him, but had come to late to save Hanzo.

Back at Otori Mountain, Hanzo asks Kagetomo whether it was the chief's emblem that he desired. However, Kagetomo says that he would not steal it, but instead, Hanzo would give it to Kagetomo at tomorrow's festival and announce him the new chief. In the meantime, one of the villagers had found where Hanzo was being held captive. Heidayu notices this and tells Kagetomo. However, Kagetomo is unfazed, and reveals that it was all part of his plan. Ash and the group, along with Sanpei, his brothers, Shinobu, and some villagers, begin to head off to Otori Mountain. Along the way, Heidayu and some of his ninja subordinates intercept them. Nihei says to Saizo that they will handle things here while Saizo and Ippei go on. A raging battle then starts between Heidayu's ninja force against Ash and his friends. Ash brings out his Pikachu and Frogadier while Sanpei brings out his Greninja. Both again battle Heidayu and his.

During that time, Saizo and Ippei have reached Hanzo, and Kagetomo challenges Ippei to a battle. Kagetomo states that the winner of the battle will become chief over the Ninja Village. Ippei's Greninja and Kagetomo's Weavile then begin a fierce battle. On the other side, Ash and Sanpei are having trouble defeating Heidayu's Bisharp. After knocking Pikachu, Frogadier, and Greninja with, Bisharp runs to attack the injured Pikachu with. However, before the attack lands, jumps ahead of  and pushes back Bisharp. As it does so, Frogadier evolves into. Ash's evolved Greninja then attacks with its newly learned and thereafter transforms into Ash-Greninja for first time. It then quickly defeats Bisharp with an extremely powerful and then reverts back to its original form before Ash could understand what had happened. ,, Nihei and Shinobu then readily defeat the other ninjas.

Meanwhile, Ippei is facing difficulty battling Kagetomo's. Hanzo silently appreciates Weavile's power but says that it lacks one thing which Ippei has. As the battle continues, Ash and the rest arrive to see Ippei battling Kagetomo. Ippei's Greninja uses which Weavile promptly removes with a powerful. However, in that time, Greninja emerges from the ground to attack Weavile. It then finishes off with Water Shuriken, defeating Weavile. While Kagetomo becomes angry at Weavile, Hanzo tells Kagetomo that his Weavile is far stronger than Ippei's Greninja. But Hanzo mentions that Kagetomo lacks one thing Ippei has, that is, devotion for the dreams of the people, Pokémon, and even the whole world.

Back at the village, Hanzo declares Ippei as the new village chief as he passes the chief emblem to him. Later, Kagetomo with Heidayu, Hanzo and Ippei, accepts his mistakes and decides to dedicate his powers for the world. For this, Kagetomo decides to go off on a journey to explore the world. He then tells Ippei to take care of the village before leaving with Heidayu. Next morning, Ash and his friends leave the Ninja Village with their best wishes. After they leave, at the underground monument for the village hero, Nihei tells Hanzo, Ippei and Saizo about Ash's Greninja's mysterious transformation. Ippei mentions that this must mean the hero from the past had saved the village again.

Major events

 * 's evolves into  and learns.
 * Ash's Greninja transforms into Ash-Greninja for the first time, though no one is aware of it.

Pokémon debuts

 * Ash's Greninja (Ash-Greninja; official)

Humans

 * Jessie
 * James
 * Sanpei
 * Ippei
 * Nihei
 * Saizo
 * Shinobu
 * Kagetomo
 * Heidayu
 * Ninjas
 * Ninja Army
 * Shinobu
 * Kagetomo
 * Heidayu
 * Ninjas
 * Ninja Army

Pokémon
Who's That Pokémon?: (US and international) Pokémon Quiz:  (Japan)
 * (evolves)
 * (Ash-Greninja; newly evolved)
 * (Ippei's)
 * (Nihei's)
 * (Saizo's)
 * (Shinobu's)
 * (Kagetomo's)
 * (Heidayu's)
 * (Ninja's; ×6)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's; ×2)
 * (Ninja's; ×3)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's)
 * (Squishy)
 * (painting)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's)
 * (Ninja's)
 * (Squishy)
 * (painting)

Trivia

 * Poké TV: "Burn! Pokémon Challenge!!" focusing on
 * and narrate the preview of the next episode.
 * In Japan, this episode aired almost exactly one year after the episode where 's evolved into.
 * This was Mika Kanai's final episode as . From the next episode Mariya Ise returns from her maternity leave.
 * The other two possible answers during this episode's Pokémon Quiz were and  which, like Greninja, are two other Pokémon known for having ninja-like abilities.
 * This is the 900th episode of the main if Holiday Hi-Jynx and Snow Way Out! are counted as episodes.

Errors

 * After Ash's friends notice, can be heard despite not being physically present and Bonnie's bag being closed. This was fixed in the dub.
 * When Hanzo, Saizo and Ippei talk to Kagetomo after Ippei defeats him, the golden triangle in Kagetomo's chestplate is colored black instead of gold.
 * After returning to the Ninja Village, the webs on both Ash's and Sanpei's 's feet are missing.
 * At the end of the episode, as Ash and his friends walk away, the patch of brown fur on 's tail is missing.
 * When Ash takes out his Pokédex, it is already open. However, when it is pointed at Ash's Greninja, it opens up again.

Dub edits

 * After evolves into, Serena says "Next time it'll be our turn, Braixen", referring to her desire for Braixen to evolve. In the original, she simply calls for Braixen to prepare to attack, but in the Polish dub, Serena says it was their turn to attack.
 * When, , and Squishy are cheering, the order of Dedenne's speaking is different in the dub compared to the original Japanese version.

In other languages
Ein Festival der Entscheidung! EP903 XY100 XY099 XY編第100話 精灵宝可梦 XY 第99集