Shuriken Gattai Shurikenjin

"Soiya Soiya! Wasshoi Ninja! Soiya Soiya! Wasshoi Ninja! Shurikenjin!"

- Shurikenjin combination

Shuriken Gattai Shurikenjin (手裏剣合体シュリケンジン) is the main Giant Robo of the Ninningers. It is made up of five OtomoNin (オトモ忍).

Overview
Shurikenjin is formed when AkaNinger spins his OtomoNin Shuriken in the Ninja Ichibantou and the Shuriken Combination (シュリケン合体) is announced. During so, Shinobimaru assists the other OtomoNin in their transformation into a giant exosuit/throne, where it sits in place and a giant OtomoNin Shuriken: Red is then placed on its head and a mask covers its face, forming Shurikenjin.

Shurikenjin's main arsenal are the the Drago Sword (ドラゴソード) and the Drago Shield (ドラゴシールド).

Shurikenjin's finisher attack is Shurikenjin: Splendid Slash (シュリケンジン・アッパレ斬り), where the Drago Sword charges with an energy and slashes the opponent.

Certain Nin Shurikens were shown able to grant Shurikenjin special moves. Among them are:
 * Kakuranger: Uses the Ninja Art: Cloning Technique (忍法・分身の術), utilizing NinjaRed's special ability of creating clones/illusions of itself onto the target before striking them.
 * Hurricaneger: Uses the Super Ninja Art: Air Gallop (超忍法・空駆け), utilizing HurricaneRed's aerial superiority where Shinobimaru temporarily ejected to move faster and rapidly strike the opponent.

History
The Companion Ninjas were first created as Nin Shuriken by Yoshitaka Igasaki after knowing that his grandchildren would face giant Youkai or other gigantic enemies. He also require helps from various alien races, using alien technology (mainly UFOmaru as it's design basis) in the OtomoNin creations, as well as using their likeness into it.

OtomoNin Shinobimaru
"Dare ja, dare ja?! Da~re, dare ja?! Dare ja, dare ja?! Da~re, dare ja?! Shinobimaru!"

- Summoning announcment

OtomoNin Shinobimaru (オトモ忍シノビマル) is AkaNinger's personal OtomoNin, taking the appearance of a humanoid mecha. When piloting Shinobimaru, AkaNinger positioned himself on the left shoulder. This OtomoNin's special ability is to create hidden traps or passages, making it a giant ninja. It is also fleet-footed, allowing it to run at great speeds, as well as run up building sides and being agile enough to leap-frog over enemies. For offense, it mainly uses speed to get in close for melee attacks. Shinobimaru can also use an invisibility cloth to cover his appearance.

Shinobimaru forms the main part of the Shurikenjin formation as the main controlling unit. He can also temporarily separate from the formation to outsmart the opponent.

When other mechas take over its position of Shurikenjin's controller and chest piece, Shinobimaru can become either the resulting formation's left hand or right hand.

OtomoNin Dragomaru
"Dare ja, dare ja?! Da~re, dare ja?! Dare ja, dare ja?! Da~re, dare ja?! Dragomaru!"

- Summoning announcment

OtomoNin Dragomaru (オトモ忍ドラゴマル) is AoNinger's European dragon-themed OtomoNin. When piloting Dragomaru, AoNinger usually positioned himself at Dragomaru's upper torso. By itself, it can fly with its wings and emit hot flames from its mouth.

During the main Shurikenjin formation, Dragomaru becomes the left hand of Shurikenjin, with its tail being used as the Drago Sword and his wings combining into the Drago Shield. During the Shurikenjin Drago formation, Dragomaru become the chest piece, with the tail and wings being placed on the formation's back to give the combination its flight capabilities.

In its first appearance, Dragomaru was shown riding a giant blue kite in place of his wings before flying on its own. This is a nod to certain ninjas that use kites as aerial transportation. The kite riding position was shown again in Shinobi 11, where AoNinger used his magic to help Dragomaru escaped from Rodeomaru's lasso before reverting back to it's original position.

Dragomaru as well had it's own finisher attack, Drago Tornado (ドラゴトルネード), where he flies around the target, creating a blue energy tornado which eliminates them, as seen on Giant Youkai Gashadokuro.

OtomoNin Dumpmaru
"Dare ja, dare ja?! Da~re, dare ja?! Dare ja, dare ja?! Da~re, dare ja?! Dumpmaru!"

- Summoning announcment

OtomoNin Dumpmaru (オトモ忍ダンプマル) is KiNinger's personal dump truck-themed OtomoNin. KiNinger usually positioned himself at the front of the truck somewhere above where the cabin is. By itself, it can toss explosive  at its opponent via two small sub-arms. It can also store large rocks on its back to throw it onto the opponent. For defensive method, Dumpmaru can initiate Dump Tatami Shield (ダンプ畳返し), where it lifts up a corner of the floor that turned into a piece of tatami floor before returning to normal.

When forming Shurikenjin or Shurikenjin Drago, Dumpmaru becomes the torso and right arm. When an auxiliary mecha take Shinobimaru's place in other Shurikenjin formations, the Dumpmaru arm will be swapped with Shinobimaru, with said right arm being stored on the back. However, if Shinobimaru is occupied with his own problem, said extra arm would take his place.

OtomoNin Wanmaru
"Dare ja, dare ja?! Da~re, dare ja?! Dare ja, dare ja?! Da~re, dare ja?! Wanmaru!"

- Summoning announcment

OtomoNin Wanmaru (オトモ忍ワンマル) is ShiroNinger's ninken (忍犬)-themed OtomoNin. ShiroNinger positioned herself at the dog's back. By itself, it can used the Kunai that hold onto its mouth to attack the opponent. Wanmaru usually rides on Byunmaru's back portion, as it also hides there.

It can also emit high-frequency howls, as was first shown in the battle against Youkai Yamabiko.

During the Shurikenjin formation, Wanmaru docks itself to the left leg that Byunmaru formed.

Wanmaru's name contains "wan" (ワン), the Japanese onomatopoeia of a dog's bark.

OtomoNin Byunmaru
"Dare ja, dare ja?! Da~re, dare ja?! Dare ja, dare ja?! Da~re, dare ja?! Byunmaru!"

- Summoning announcment

OtomoNin Byunmaru (オトモ忍ビュンマル) is MomoNinger's magnetic levitation train-themed OtomoNin. MomoNinger positioned herself at the top of the cockpit. By itself, it can launch giant shurikens shaped like her visor at the enemy, as well as having the ability to travel upside down. It also carried along ShiroNinger's Wanmaru.

As Shurikenjin, Byunmaru forms the legs.

Byunmaru's name contains "Byun" (ビュン), the Japanese onomatopoeia of "going fast".

Shurikenjin Drago
"Drago! Drago, Wasshoi! Drago! Drago, Wasshoi! Shurikenjin Drago!"

- Shurikenjin Drago combination

Shurikenjin Drago (シュリケンジンドラゴ) is the alternate form of Shurikenjin formed when Dragomaru switches place with Shinobimaru.

Much like Shurikenjin, once the Shuriken Combination (シュリケン合体) is announced, this time by AoNinger spinning his OtomoNin Shuriken in the Ninja Ichibantou, Shinobimaru switches places with Dragomaru, where Shinobimaru becomes the left hand and Dragomaru sits in the exosuit and a giant Otomin Nin Shuriken: Blue is placed on its head, creating a larger dragon head and forming Shurikenjin Drago.

Shurikenjin Drago can participate itself in an aerial combat against aerial-themed opponents and can release fire from its mouth. It can also use its razor-sharp wings to slice at an opponent, as well as using its tail to attack.

Shurikenjin Drago's finisher attack is Shurikenjin: Drago Burst (シュリケンジン・ドラゴバースト), where it fires a stream of energy, aiming it at the ground then lifts up to carve a path of destruction to the unfortunate Youkai standing in the attack's war path.

Shurikenjin Paon
"Paon, Paoooooon! Wasshoi! Paon, Paooooooon! Wasshoi! Shurikenjin... Paooooon! (Indian musical fanfare)"

- Shurikenjin Paon combination

Shurikenjin Paon (シュリケンジンパオーン) is the alternate form of Shurikenjin formed when Paonmaru takes over Shinobimaru's place with the OtomoNin placed into the formation's right hand, while the giant OtomoNin Shuriken: Paon is placed on the head in place of the Shinobimaru one. This is performed when AkaNinger spins his OtomoNin Shuriken: Paon in the Ninja Ichibantou and the "Shuriken Paon Combination" (シュリケンパオーン合体) is announced. This form specializes in power-type attacks.

Shurikenjin Paon is armed with twin Paon Axes (パオンアックス) formed by Paonmaru's rear feet (machine cannons in its Humanoid Form) to hack at the giant Youkai, while the Paon Jet (パオンジェッ) used in the Normal OtomoNin form can also be used here to injure it before the finisher.

Shurikenjin Paon's finisher is Shurikenjin: Paon Boomerang (シュリケンジン・パオーンブーメラン), where the twin Paon Axes are thrown at the giant Youkai creating a X-slash before returning to the arms of Shurikenjin Paon, just like a pair of returned boomerangs.

In Shinobi 15: Youkai, I Never Failed, an alternate version of Shurikenjin Paon is seen with Dumpmaru's arm instead of Shinobimaru as the latter had left with AkaNinger to battle Rodeomaru, who was under Youkai Futakuchi-onna's control.

Shurikenjin UFO
"UFO Was-shoi! UFO Was-shoi! Shurikenjin... UFO! (Dramatic space fanfare)"

- Shurikenjin UFO combination

Shurikenjin UFO (シュリケンジンUFO) is an alternate form of Shurikenjin formed when UFOmaru takes over Shinobimaru's place with the OtomoNin placed into the formation's right hand, while the giant OtomoNin Shuriken: UFO is placed on the head in place of the Shinobimaru one. This is performed when AkaNinger spins his OtomoNin Shuriken: UFO in the Ninja Ichibantou and the "Shuriken UFO Combination" (シュリケンUFO合体) is announced.

This form gives Shurikenjin a flight boost and gives Shurikenjin the ability to chase down and battle enlarged Youkai that are capable of extra-atmospheric or even zero-gravity combat, patching up Shurikenjin Drago's limitation of flying only within the Earth's Atmosphere.

Shurikenjin UFO is armed with the UFOmaru Launcher (UFOマルランチャー), which typically is used as a short trident lance during normal combat to injure the enlarged Youkai before launching the finisher.

Shurikenjin UFO's finisher is Shurikenjin: UFO Big Bang (シュリケンジン・UFOビッグバン), where the robot charges up the UFOmaru Launcher to fire three guided Nin Shurikens which strikes the target in all directions to defeat the Giant Youkai, forming the Ninningers' insignia in the process.

In Shinobi 15: Youkai, I Never Failed, an alternate version of Shurikenjin UFO is seen with Dumpmaru's arm instead of Shinobimaru as the latter had left with AkaNinger to battle Rodeomaru, who was under Youkai Futakuchi-onna's control.

Empty Shurikenjin
A version of Shurikenjin with an unoccupied controller appeared when UFOmaru was erased from existence due to the Ninningers being taken to the Kamen Rider dimension.

It was later shown again when Shinobimaru, AkaNinger, AoNinger and MomoNinger exit Shurikenjin to save Kinji and Rodeomaru from Youkai Futakuchi-onna, thus leaving Shurikenjin unpiloted until KiNinger and ShiroNinger summon Paonmaru and UFOmaru.

Shurikenjin Tridoron
Shurikenjin Tridoron (シュリケンジントライドロン) is the alternate form of Shurikenjin formed when it combines with Tridoron after it is converted into an OtomoNin by the Tridoron Shuriken.

Much like the original Shurikejin, Shurikenjin Tridoron's main arsenal are the Drago Sword (ドラゴソード) and the Drago Shield (ドラゴシールド).

Shurikenjin Surfer
"Surfin'! Wasshoi! Surfin'! Wasshoi! Shurikenjin Surfer! (Guitar solo beach fanfare)"

- Shurikenjin Surfer combination

Shurikenjin Surfer (シュリケンジンサーファー) is an alternate form of Shurikenjin formed when Surfermaru takes over Shinobimaru's place with the OtomoNin placed into the formation's right hand, while the giant OtomoNin Shuriken: Surfer is placed on the head in place of the Shinobimaru one. This is performed when AkaNinger spins his OtomoNin Shuriken: Surfer in the Ninja Ichibantou and the "Shuriken Surfer Combination" (シュリケンサーファー合体) is announced.

In this formation, Shurikenjin retains the Drago Sword (ドラゴソード) as a side weapon while given a surf board that Surfermaru rides. The mecha is capable of manipulating tidal waves to increase it's advantage in surfing on the ocean.

It's finisher attack is Shurikenjin: Surfer Surfing Slash (シュリケンジン・サーファー波乗り斬り), where Shurikenjin Surfer surfs into the enemy and slashing it with Drago Sword.

Shurikenjin Dino
Shurikenjin Dino (シュリケンジンダイノ) is an alternate form of Shurikenjin formed when Dinomaru takes over Shinobimaru's place with the OtomoNin placed into the formation's right hand, while the giant OtomoNin Shuriken: Dino is placed on the head in place of the OtomoNin Shuriken: Red one. This is performed when AkaNinger spins his OtomoNin Shuriken: Dino in the Ninja Ichibantou and the "Shuriken Dino Combination" is announced.

Shurikenjin Texas
Shurikenjin Texas is an alternate formation of Shurikenjin where Rodeomaru takes the place of Shinobimaru. As of now, this formation is only described in the instructions for the Bison King toy and has not appeared in the show itself or any associated movies or specials.