Susano'o

When activated, Susanoo forms around the user and becomes an extension of their will, acting and attacking on their behalf. By default, Susanoo is anchored to its user and they to it: in its less developed forms it will move around with the user; in its more completed forms the user will be suspended within Susanoo, being brought with it as it moves around. This connection allows Susanoo to shield against physical attacks, one that becomes more difficult to penetrate as it is manifested more fully. If it is damaged, Susanoo does not regenerate and it can only be repaired either by advancing it to the next developmental stage or by dispersing it and then forming it anew.
Although Susanoo is quite effective as a defense, it is able to distinguish in what it blocks. For example, the user can still perform jutsu while within Susanoo and the attacks will pass through it without complications. Others can be brought within Susanoo with the user's permission, and users can likewise choose to leave Susanoo's protective envelope. The latter property can be used against the user, as if an opponent can bypass Susanoo, however slightly and latch onto them, they can be pulled out of Susanoo. With continued mastery, Susanoo can have increased defensive capabilities even at its ribcage stage, as seen when A was able to crack a rib of Sasuke's Susanoo, but could not even crack Madara's. Susanoo is also only able to defend against physical attacks, so they are still vulnerable to visual or auditory attacks. Also, unless the legs of the Susanoo are fully manifested, the user's still vulnerable to attacks from below.
== Susano'o Stages ==
As seen with Sasuke's learning how to use it, Susanoo has several developmental stages. Practised users go through all the stages every time they manifest it, layering more advanced stages over earlier ones or stripping them away as is needed; they can choose to stop at any developmental stage. At its simplest level, users only manifest aspects of Susanoo's skeletal structure, such as a ribcage for basic defense or an arm for interacting with the surroundings. Once a full skeleton is made, musculature and, later, skin forms until finally a complete humanoid is shaped. In these early stages, typically only the upper half of Susanoo is materialized, with legs becoming common once it reaches its full humanoid form; however, not all Susanoo users can accomplish the latter feat.
=== Ribcage ===
Ribcage: You are treated as having cover against incoming attacks (+4 to AC, +2 refllex). You are still treated as a medium sized character and the Susano'o uses your base attack bonus and unarmed damage but scaled up by one step (character with 2d10 damage deals 4d6 points with their Susano'o). Using Susano gives a character a 15 foot reach with their attacks. The character gains DR equal to their constitution ability. This DR applies to both jutsu and physical attacks, and the Susano'o can block a number of attacks equal to the character's Wisdom Modifier before breaking, otherwise a Susano'o lasts for however long the user has chakra to keep it manifested. Manifesting Susano'o ribcage costs 5 chakra per round, on top of the cost of manifesting a Mangekyou Sharingan.
=== Humanoid ===
Musculature/Skin: Same as Ribcage, except you are treated as a Large creature. Attacks are made with a -1 penalty and your character cannot be attacked directly. Instead the Susano'o becomes the target of all the attacks, having an HP pool of your maximum chakra amount. It uses your AC and saves, as modified by your new size. Essentially the Susano'o becomes the new character that you control. In this form you lose the use of your weapons and unarmed attacks, though you can still use jutsu with a range farther than touch. In this stage a Susano'o still can be attacked from below, and ground-based attacks can affect the character inside, this is treated as targeting a specific area of the construct. As a large creature, the Susano'o is treated as having a dex -2 and a Strength +2 from your own scores. Manifesting this version of the Susano'o increases the cost to 10 chakra per round.
=== Armored Susano'o ===
Same as Humanoid, except the Susano'o manifests weapons and armor. The armored Susano'o has a natural armor bonus to its AC equal to the highest level of jutsu the manifester of the Susano'o can cast. Weapons manifested through the Susano'o are considered Huge weapons and deal increased damage from the basic version used by most characters, you are treated as a Huge character as well. A character's weapons in the Susano'o have an enhancement bonus equal to the character's level/10 (minimum +1). Such manifested weapons cannot have different effects applied to them, they simply give a bonus to the attack and damage. The armored Susano'o has DR equal to half your character level/2. Manifesting an Armored Susano'o costs the user 15 point of chakra per round.
== Eternal Mangekyou Sharingan ==
Obtaining the Eternal Mangekyou Sharingan allows the user to progress their Susano'o, as well as reduces the cost of manifesting it. Eternal Mangekyou gives additional stages of manifestation.
Ribcage
Ribcage: You are treated as having cover against incoming attacks (+4 to AC, +2 refllex). You are still treated as a medium sized character and the Susano'o uses your base attack bonus and unarmed damage but scaled up by one step (character with 2d10 damage deals 4d6 points with their Susano'o). Using Susano gives a character a 15 foot reach with their attacks. The character gains DR equal to their constitution ability. This DR applies to both jutsu and physical attacks, and the Susano'o can block a number of attacks equal to the character's Wisdom Modifier before breaking, otherwise a Susano'o lasts for however long the user has chakra to keep it manifested. Manifesting Susano'o ribcage costs 1 chakra per round, on top of the cost of manifesting a Mangekyou Sharingan.
=== Humanoid ===
Musculature/Skin: Same as Ribcage, except you are treated as a Large creature. Attacks are made with a -1 penalty and your character cannot be attacked directly. Instead the Susano'o becomes the target of all the attacks, having an HP pool of your maximum chakra amount. It uses your AC and saves, as modified by your new size. Essentially the Susano'o becomes the new character that you control. In this form you lose the use of your weapons and unarmed attacks, though you can still use jutsu with a range farther than touch. In this stage a Susano'o still can be attacked from below, and ground-based attacks can affect the character inside, this is treated as targeting a specific area of the construct. As a large creature, the Susano'o is treated as having a dex -2 and a Strength +2 from your own scores. Manifesting this version of the Susano'o increases the cost to 3 chakra per round.
=== Full Body Susano'o ===
Manifesting the Full Body Susano'o is like the humanoid. You fully encapsulate yourself in a construct of chakra. You are treated as Huge size (-2 to AC, +4 to Strength, -4 to Dex). The Susano'o uses your base stats, as in the humanoid version, though the unarmed damage is stepped up two dice (2d10 becomes 4d8 unarmed damage). You can also not be the target of incoming attacks, instead they can only target Susano'o itself. Manifesting full body Susano'o costs 5 chakra per round. A character able to manifest Humanoid Susano'o may choose to manifest Full Body instead, at the higher cost. 
=== Armored Susano'o ===
Same as Humanoid, except the Susano'o manifests weapons and armor. The armored Susano'o has a natural armor bonus to its AC equal to the highest level of jutsu the manifester of the Susano'o can cast. Weapons manifested through the Susano'o are considered Large weapons and deal increased damage from the basic version used by most characters. A character's weapons in the Susano'o have an enhancement bonus equal to the character's level/10 (minimum +1). Such manifested weapons cannot have different effects applied to them, they simply give a bonus to the attack and damage. The Armored Susano'o has DR equal to your character level/2. Manifesting an Armored Susano'o costs the user 10 points of chakra per round.
=== Perfect Susano'o ===
The pinnacle of power, the perfect Susano'o rivals the power of tailed beasts. It is like Armored Susano'o, except you are treated as Gargantuan (-4 AC, +6 strength, -4 to dex). Unarmed damage is stepped up by 3 dice (2d10 becomes 4d10 base damage for unarmed attacks). The weapons and armor on this manifestation have an enhancement bonus equal to your character level/5 (minimum +1). The Perfect Susno'o has DR equal to your character level. Such manifested weapons cannot have different effects applied to them, they simply give a bonus to the attack and damage, unless the wielder has taken the Improved Weapons feat. Manifesting an Armored Susano'o costs the user 15 points of chakra per round.
In order to manifest a higher version of Susano'o the character must first have manifested the on preceding to it on this list. (In order to manifest armored version, the character must have manifested humanoid on the previous round, etc.).