Senjingan

Senjingan is the dōjutsu of the Batista Clan. It began as an artificial dōjutsu, but was essentially converted into a kekkei genkai that could be passed down genetically by its inventor, Kittu Batista.

Background
Batista used medical ninjutsu and fuuinjutsu to alter the small scale structure of his retinas, specifically its rods and cones, to resemble the structure of a certain organic substance, often referred to as frozen smoke, that has an internal makeup with extremely high surface area. One gram of frozen smoke can easily hold a surface area equal to the entire stadium used to host the chuunin exams. The retina of the normal human eye possesses a surface area of 43 inches square. The rods and cones of one eye of the senjingan possess the surface area of 1 acre or 44,000 square feet.

Abilities
The lens of the senjingan has also been altered so that any light that passes through becomes encoded and written on the retinas as seals. In other words, a photorealistic image of anything the eye witnesses is sealed on the all but limitless surfaces of the senjingan retina as simple symbols. Every waking second of the senjingan users visible life is recorded and perfectly preserved in his eyes. A clansman can also playback a mirage of anything he has seen in his mind or project such a mirage visible to others. He can do this simply by recalling it as he would any memory, while focusing a small amount of chakra to his eyes. Because of his doujutsu a clansmen has total recall.

This is nothing like the sharingan’s jutsu copying ability. This feature of the senjingan offers the user not much more than would a portable high definition video camera similar to the closed circuit television cameras used to monitor combatants during the chuunin exams. The only difference in capability is their almost limitless storage capacity and both external and internal 3D playback capabilities. Without the photographic reflexes afforded to sharingan users one cannot simply copy jutsu with the senjingan. However, given it’s playback abilities a senjingan user has the ability to study what it witnesses later in infinite detail more easily with more flexibility than rewinding and reviewing a video tape. As the members of the Batista clan specialize in combat fuuinjutsu and illusion casting, their eye’s photographic memory gives them an extensive library of sealing jutsu. Their experts can study any seal they’ve ever witnessed at any time of their leisure for as long as it takes to understand the seal’s inner workings and replicate them, similar to how master sealer Jiraiya studied the 4th‘s Shiki Fuujin and Orochimaru‘s Gogyō Fūin to decipher their secrets.

Since the total retinal surface area of the senjingan is 88,000 square feet, greater than all the books and scrolls in Konoha’s public library, the primary capability of the senjingan allows it to seal anything that can be sealed in a scroll directly in the retinas as if they were scrolls. First the senjingan projects a full-scale visual representation of the necessary seal somewhere in the visual field, makes a hand seal and summons the chakra appropriate to the object being sealed. The target is absorbed into the mirage as it would be if sealed in a scroll, then the illusion of the seal is reabsorbed into the eye. The target exists from that point as a symbol written on the retinas of the senjingan.

In order to unseal these objects the image of the matching unseal mark must be projected anywhere in the visual field as the necessary hand signs performed and chakra summoned for the intended unsealing jutsu. When in combat the unsealing and attack are simultaneous actions. This technique is known as battokiri after the technique of quickly drawing a sword and attacking in the same motion. Weapons, supplies, deadly objects and substances, and even living entities can be sealed within the senjingan, though this is an extraordinarily complex process to be performed by a jounin or kage level holder of the senjingan.

When working with live summons, lower level clansmen utilize summoning seals by marking a summons with a seal corresponding to a seal written with their senjingan. They can then summon and control a creature with during combat. The senjingan is a method of sealing only as powerful as it's user. In order to successfully seal any object with the senjingan, the user must posses the chakra capacity and skill set to seal that same object with conventional fuuinjutsu. Furthermore, the user must have developed the necessary degree of facility with the techniques specific this doujutsu: gathering toton chakra in the eyes, executing encoded hand signs, projecting sealing mirages, burning seals, and battokiri, the simultaneous projection/activation of unsealing marks or summoning seals and the coordination of associated attacks.

Usage
The difficulty of sealing objects with the senjingan directly correlates with the object's complexity.

Information: Storing information is the primary goal that led to it's creation. Storing any and all types of information is effortless with the senjingan.

Inanimate Objects: Motionless objects are easily sealed with the senjingan. This is the first level of combat fuuinjutsu used by senjingan clansmen. This method of sealing objects and fighting is very similar to the way Ten Ten fights. However, this clan also combines these methods with paper manipulation and origami techniques similar to Konans. If it is sealed immediately, a dead body is considered an inanimate object. This technique is often used to preserve corpses. Dead bodies undergoing an advanced state of decay have to be sealed as animate objects. Genin can usually seal most kinds of inanimate objects.

Animate Objects: Animate objects can also be sealed along with their defining physical characteristics. This means that objects in motion and undergoing change can be sealed along with their changing attributes. A fire can be sealed or the water rushing through a river or molten lava. Clansmen use this technique in combat to attack with flowing water or blazing fire. Even lightning from thunderstorm can be captured and sealed under the appropriate circumstances though this is not an easy task. Chakra sealing also becomes available at this level. Chuunin are just starting to become adept at this kind of sealing.

Golems: Non-living animated avatars which can act autonomously are referred to as Golems. They are a subclass of animate objects as they have no life processes or intelligence of their own. They can be imbued with animal like instincts or directly controlled with a senjingan seal. Golems are often used instead of summoning living creatures as they are easily sealed as animate objects with less chakra than summoning techniques. Golems are most often constructed out of chakra metal or other chakra resonant material. Chuunin are capable of creating, sealing, releasing, and utilizing golems.

Spiritual Entities: Demons, ghosts, and other spiritual entities can be sealed. However, only a small number of these entities can be sealed as it is inordinately stressful on the system. Jounin and beyond are qualified for this type of sealing.

Living Creatures: Non-sapient animals can be sealed, however, this is an extraordinarily stressful and difficult process. Even when attempted by experienced ninja can result in injury and death. For this reason living organisms are usually summoned and controlled rather than sealed. Animals and other creatures can be marked with a summoning tattoo. This tattoo serves to both call forth a creature and control it for the duration of use. Unlike blood contracts the summoned entity acts solely under the control of the user. Chuunin can and do use summoning seals. Only high jounin and above dabble in sealing living creatures.

Sapient Organisms: Thinking creatures with living physical forms are almost impossible to seal in this manner. Although, it is rumored that a person can be placed in a state of suspended animation and sealed or that the soul can be stripped from the body and the two sealed separately in the manner of spiritual entities and inanimate objects to be unsealed and rejoined at a later date. However, any such suspending, stripping, and rejoining processes remain unknown among the clansmen at the present time. However, sapient creatures can easily be summoned. Sapient creatures are not usually controlled unlike mindless animals. Although, these methods exists, they are considered heinous and are forbidden by clan leaders. Sapient creatures are therefore summoned with their permission often by way of a contract system similar to the usual.

Sapient creatures are often tagged for summoning. These summoning seals are usually more temporary than blood contracts for limited usage. Chuunin level and above are capable of this kind of summoning with senjingan seals. There is a special type of creature in this class used by Kage level members of the Batista clan. Human beings and sapient animals can be killed, part of their body kept alive so they may be turned into golems, similar to the human puppets used by Sasori, and then sealed. The golem will have no personality of its own, but a portion of the user's spiritual energy is sealed within the golems brain. The golem will think and act on it's own, using the chakra and jutsu of the original body's owner. The only known living user of this jutsu is the current leader (NPC) of the Batista Clan.

Drawbacks
The senjingan places an inordinate amount of stress on the system. Lifetime usage leads to a rare disorder unique to members of the Batista clan and their eye transplant recipients. They refer to this disorder as mokumokuren. Those afflicted with this condition gradually lose control of their senjingan sealing abilities. This can lead over time to neural seizures causing the spontaneous unsealing of objects or projection of sealed information. Early on this can be alleviated simply by closing or covering the eyes. However, as the degenerative disorder progresses, the level of toton chakra generated in the senjingan becomes intense enough to burn through the eyelids or bandages covering them. At this point it is dangerous to the user and everyone around him. It becomes necessary to unseal the entire senjingan inventory and seal the senjingan permanently so that it loses it's abilities. The sealed user can still see and function normally. However, since his total recall is based upon his doujutsu, he loses that ability and usually undergoes rehabilitation to retrain him to use his memory normally.