The Shippai belong to Sunagakure no Sato. A clan which sprung to life when another clan, the Chikamatsu clan, managed to place a soul inside a metal puppet. While the clan members suffers from memory loss they are, what some consider, perfect soldiers.
Due to the massive amount of various mental defects the entirety of the clan it is a stretch to say that the clan has any sort of ideology of their own, primarily due to the mass majority of their clan being unable of even thinking for themselves. However, that is not to say that the clan is without any sort of purpose, merely that the purpose they have is not one they chose for themselves.
Previously the clan's sole purpose was to ensure the survival of the Chikamatsu clan who acted as their masters for over a hundred and fifty years before Sunagakure even came to be. Upon the village's formation the Shippai were gifted to the first Kazekage of Sunagakure and their new standing orders replaced their old ones. It is those olders which stands now and it is those orders that serve as the creed of the clan.
Rule #1 - Kill any threat to Sunagakure. Rule #2 - Carry out any order issued to you by the Kazekage.
The Shippai is a clan which has existed for roughly two-hundred years. Unlike many clans which form when a group of people show a bloodline trait or teach themselves a power technique, the Shippai's existence was caused by a massive amount of failures, hence their name.
Long ago when the Chikamatsu clan first pushed the boundaries of puppetry techniques and dived into the taboo realm of human puppetry two techniques were created. The first was based on the concept of using the bodies of humans as puppets and ridding the bodies of the souls they held, keeping only the abilities the body had used in life. The second technique was the opposite side of the same coin. . . to do away with the fleshy human body and instead keep the soul, placing it within a new metallic body.
It was this later technique's many, many failed test subjects that make up the entirety of the Shippai clan. The Chikamatsu soon discovered that that particular technique had a success rate of only one in a thousand. Thankfully or perhaps regretfully depending on who is asked, the Chikamatsu decided to keep their failures alive and use them as a small army of sentinels.
While these failure's minds had by and large been shattered by the process, they were still capable of following simple orders. Adding in their metal bodies, unflagging endurance and impressive strength alongside their not needing to sleep and they proved to be valuable guards for the clan's compound and the desert surrounding it. Originally the clan numbered roughly eighteen hundred members. By the time the Chikamatsu joined Sunagakure and gifted the Shippai to the village they numbered roughly fifteen hundred.
While the Chikamatsu had quickly grown accustomed to the Shippai through the years, the population of Sunagakure saw them as freaks, abominations or for a few, as victims who should have been put out of their misery long ago. To help acclimate the general population to the Shippai, they were no longer referred to as people or even clan members. Instead they were simply referred to as units, stripped of their names and instead given a simple number which allowed most people to disassociate them as having been human beings at one point. It was a matter where everyone knew the truth, but this small lie would allow them to pretend everything was fine. Naturally though, none of the Shippai cared, few of them could care and the ones who could rarely could continue to care more than a few moments.
For the Shippai, their history from that point on has just been one of service to the village. As the years went by and the village found itself taking part in the First Shinobi War, then the Second followed shortly by the Third; the Shippai clan found its numbers diminishing as they were used as sacrificial tokens. Most shinobi within Sunagakure figured it was better for a Shippai to die and take as many enemies with them as possible rather than for a shinobi of Sunagakure to die.
This thought process was embraced even more wholeheartedly after an event which occurred in the window of peace between the First and Second Shinobi Wars. Up until that point all Shippai clan members had, had a third standing order; to protect themselves from any attack. One afternoon however, a group of Sunagakure children had decided to mess with one of the Shippai workers who moved through the streets hauling large stones to a worksite. They smacked the Shippai unit's helmet off of its body and had planned to play a game of keep away with the creature.
The unit however, took this action as a sign of aggression and within a brief moment the bodies of several children littered the street. Naturally, once the Shippai unit showed up at the work site with blood on it and the stones it carried, it was only a matter of time for the workers to back track and find the tiny bodies.
After this event there was a public outcry for the Shippai to be destroyed. They screamed that they were not safe with the abominations around, that they could snap at any moment. While this was somewhat true with some of the units, the majority of them had still been more than fit for service. The Chikamatsu tried to explain what had happened, but no one wanted to hear it. So, the Kazekage not wanting to lose any potential tools decided to put all the Shippai in storage until a day came where they were needed again.
The Third Shinobi War was the last time the Shippai were used in extremely large numbers. While some of them were used during the Ame-Suna conflict, the clan has thankfully been able to avoid their members or as the Suna citizens prefer, units; from dying in mass since then. As it stands the Shippai number a small three-hundred and forty-seven. This is roughly a sixth of what they were when they were originally created and since the Chikamatsu's technique which created them was declared a kinjutsu long ago the clan will never see a new member. Instead, they have been fated to simply die in place of others until they are all gone. . .
While there is no command structure between members of the Shippai clan there are two categories in which all the members fall, even if they do not always remember it. There are active duty units and repurposed units. A long time ago members of the clan were referred to as people, but after being given to Sunagakure the names were changed and the clan members simply referred to as units to make them slightly less unsettling to the general population.
For active duty units, their jobs range depending on the orders issued to them by the Kazekage or to those he decides to grant command over some of the Shippai. Primarily these units are used as guards, patrolmen for the vast desert wastes or in times of war, as disposable units for making distractions or covering retreats. This is primarily due to the major mental defects making it impossible for Shippai clan members to carry out any complicated orders. Generally, those in charge of a Shippai unit will go so far as to write their varying orders in a notebook and even carve their standing orders into their metallic bodies.
While the active duty members might be what the public sees of the clan, it is the repurposed units who make up the bulk of the clan. These units are those that were deemed unsuited to be used alongside the standard shinobi forces. Generally these pathetic shells are used for manual labor around the village. Once again, orders for them must be very simple so they are generally used to haul materials, dig wells or most recently produce electricity and pump the village's main water supply by manually turning a large turbine throughout the day.
Kugutsu Keijō means puppet form and is the trait unique to the Shippai clan and refers to the fact that the members do not have a human form, but a metallic puppet form.
Having had their souls and chakra bound to various puppet bodies, the Shippai clan has naturally been blessed with several abilities, although none of them are of their own creation or design and more importantly they have had to pay a heavy, heavy price for them.
Unflagging Endurance - The Shippai are capable of staying awake twenty-four seven, three sixty-five and in that time will never have a single moment where their alertness wanes. This of course can be argued to make them perfect guards, as they will never fall asleep on the job and can continue to operate without flagging until they have been destroyed enough to render them unable to move or more commonly, until nothing is left at all. This ability also makes them fairly well suited to long, drawn out fights as they can keep fighting on and on until their foes have died from exhaustion.
Armored Bodies - While some Shippai might have a very differently designed body, they are all definitely capable of taking far more damage than a human could ever hope to take. As there is no need for a human body to sit inside these frames, they have far more reinforcements and thicker armor than anyone could ever wear normally. This in turn makes it quite difficult to destroy most Shippai, although not impossible. It is because of this and their unflagging endurance that the Shippai were commonly used on the front lines in the Shinobi Wars.
Titanic Strength or Speed - As mentioned before, Shippai frames vary significantly. While they are all armored to some degree, some Shippai frames were purposed to have more speed by having less weight while others were built tougher and have more weight behind their blows. For some Shippai they are able to move at a blur for the naked eye (although perfectly visible to doujutsu) or are capable of creating small craters with their unarmed attacks.
Memory Loss - One of the largest blessings and curses of the Shippai is the issues they have with memories. Specifically, the Shippai's inability to store memories long term. All Shippai are only able to remember general events and people no longer than five or six months. As for more detailed matters, they are able to remember these no longer than a week or two if they're simple and direct or only two or three days if they are very minor details.
An example of this is that a Shippai clan member could remember that there was a war that ended a month beforehand, after a few more months though it's unlikely they would remember there ever was a war unless they had just been told about it again within the past week or so. As for details, they could only repeat a simple order such as "go to this town" for about a week or two. The memory of what their commander ate for breakfast would last two or three days at best.
The most important weakness that comes from this is the Shippai member's inability to learn any new techniques or abilities. Effectively they are stuck at the level their soul was transferred to their new vessel.
No Chakra Paths - While the Shippai do have chakra flowing all through them, as it powers their movements and even retain their chakra nature; because they lack any chakra pathways they are completely unable to properly mold chakra on their own or utilize any elements on their own.
This effectively means that Shippai are incapable of utilizing ninjutsu, genjutsu, fuuinjutsu, medical ninjutsu or senjutsu. Additionally, Shippai are unable to utilize any taijutsu or bukijutsu which require the user to mold any chakra for the technique and do not rely solely on physical movement. Additionally, many Shippai are unable to use very intricate taijutsu or bukijutsu techniques due to the mental limitations most of them have.
Fail Safes - Originally put in place to prevent the test subjects from betraying the clan or running off with their new bodies, after the failure became apparent the fail safes were left in place to prevent the designs of the puppets from being stolen. After the Chikamatsu shared the common puppetry techniques with the world the official reason for the fail safes being left was to kill any foreign shinobi who came upon a Shippai that had been disabled if they tried to take it apart. The truth is that is was still partially to protect the Chikamatsu clan's designs. As it stands only a master level Chikamatsu puppet crafter with access to the clan's hidden documents can safely take apart one of the Shippai.
Compulsion - To combat the memory loss, Shippai clan members have the core two rules, as well as the term standing orders scratched into their bodies. Generally these are caved into the inside of their elbows or other areas that are less likely to be damaged. Clan members are to read these orders every day and by reading them and the message stating that they're their standing orders they're able to keep these few words fresh in their minds. It is for this reason that more complicated orders are often written into journals for the Shippai.
In this regard it should be noted that a member of the Shippai will be compelled to follow whatever orders they have carved into them and if the memory is recent enough, whatever is written in their journals. Namely, protecting Sunagakure and following orders given to them no matter what the danger or morals of the order.
Crippling Clarity - While not common, a Shippai member might occasionally remember their entire history and understand their current situation with devastating clarity. While some might say it is a good thing, for the Shippai it means they have to live through hundreds of years worth of war, death, abuse and other terrible memories within the ten or fifteen seconds of clarity. These spells of clarity may never come to some, may come once every fifty years for others and for the truly pitiful even every few weeks. It is those who remember more often that are repurposed to more mundane jobs such as turning the turbine within the village.
Other Mental Defects - While not as uniform as the other issues all the Shippai have, Shippai are capable of having a large variety of additional mental defects. These range from overly aggressive natures, going unresponsive for hours at a time or even compulsive disorders that may fall in line with who that Shippai unit used to be such as inexplicably collecting trinkets.