Bijuu do not trust humanity. They're living chakra weapons and monsters created by the Sage of Six Paths. Jinchuuriki need to document bijuu personality and interactions before each progression. If you don't upgrade then you're forgotten by the bijuu, and this is mainly for future jinchuuriki. Bijuu will not info dump canon information, and have broken memories since canon story isn't finished. Jinchuuriki are considered war powers and unless in the case of rogues or village negligence they will always be accompanied by a team or jounin+ NPC if need be.

Bijuu Starting Roster
Genin is all that's needed to start with a bijuu. Characters with clans can only have a bijuu sealed into them with 5,000 words, and bijuu powers are locked until completed words. If jinchuuriki get an unethical implant after they can never access bijuu mode.

Bijuu Power
Bijuu cannot die no matter what unless their jinchuuriki dies. A released bijuu has never been shown to die. If in bijuu mode it also means the jinchuuriki sort of cannot die from new injuries unless bijuu/juubi stat strength is used to put Bijuu Mode on cooldown. Chakra Absorption and Outer Path are the only means to do anything beyond superficial damage at elder strength to jinchuuriki. Bijuu do not have all bijuu-level stats.

Their only bijuu-level stat is stamina but when released they're capable of all kinds of custom jutsu and as already noted: unkillable. Fully released bijuu (not jinchuuriki taking their form) have all elder stats except either health or instinct which is jounin.

Each Bijuu's jinchuuriki has a special power granted when they submit and that's equivalent to a custom Mangekyou. These powers are non-canon ones, except in the case of Kyuubi it's Negative Emotion Sensing which works like Sage Mode. The difference to Sage Mode is that if there are no sensors then the user needs to focus not doing anything for 1 post each time they want to use Negative Emotions Sensing. Bijuu need to submit to be mastered and this is not the same as being stronger than them. There needs to be actual threat by genjutsu or fuinjutsu that makes the bijuu want to share chakra as it cannot be forced. This won't apply to Juubi. This is also unneeded if a bond is formed with the bijuu. A bond cannot be formed if evil as the bijuu are an inherently good organization. Finally, to access chakra mode requires S-rank seals.

Tailed Beast Modes
Making a bijuu submit to helping will give most of it's power regularly. Until a bond is formed to possibly form a haori (S-rank seal) the Tailed Beast Chakra Transfers, Genjutsu Cancelling, and Tailed Beast Balls are locked to uncontrolled forms. Forming a true bond gives the option to truly transform into a controlled bijuu's flesh regardless of seal level.

Until a significant amount of times passes OOC or IC all usages of the tailed beast are capped at 10 posts per topic. Being fatally damaged in full Tailed Beast Mode places all tailed beast abilities on cooldown for 5 posts unless NATURAL bijuu-level chakra or Perfect Susanoo merges.

Jinchuuriki Power
All Jinchuuriki inherit canon bijuu abilities.
Shukaku/1 Tail - Sand Manipulation and Fuinjutsu. Magnet Release locked to mastering.
Matatabi/2 Tail - Free Fire Release in the form of Blue Fire. Cannot be used for 5 elements.
Isobu/3 Tail - Coral Release out of nothing.
Son Goku/4 Tail - Lava Release, Lava Release Armor, and no derived elements.
Kokuo/5 Tail - Boil Release limited to the body but "Unrivalled Strength" nintaijutsu that will always damage at B-rank.
Saiken/6 Tail - Non-elemental Boil Release.
Chomei/7 Tail - Flight not available to everyone on site and powder that blinds as long as targets are present.  
Gyuki/8 Tail - Ink jutsu not related to Sai.
Kurama/9 Tail - B-rank auto regeneration.

Tailed Beast Balls, Tailed Beast Shockwave, Tailed Beast Chakra Arms, and Tailed Beast Chakra Transfer are all S-rank tailed beast skills that don't require specialties for mastered jinchuuriki. Tailed Beast Titan Modes scale like regular Susanoo and are only available at true bond.

Normal Tailed Beast forms have bubbling red chakra that give levels to physical stats earlier. Every 2 tails gives 1 level as if ranking up earlier (for example, a genin would get up to jounin level stats earlier if they have Hachibi). Jinchuuriki can train their version 1 forms at 2 tails each so they get their boosts without bijuu influence. Each 2 tails requires 3,000 words training. Training is strictly graded and should have story+development beforehand.

Shukaku and Matatabi can turn into smaller versions of their full tailed beast state without drawbacks albeit the tailed beasts will have temporary control. Shukaku and Matatabi's fake full tailed beast states have +2 the same EARLIER levels after training 7,000 words. They don't give bijuu stats and otherwise use the jinchuuriki stats along with giving access to some bijuu jutsu.

Training can be done during a topic through spoilering the training content. Chakra modes require no training after the bijuu's submission and give levels in the tails regulated, or +1 level capped at elder. Bijuu abilities, sanity, and advantages that bijuu will have when in control are subjective just like the advantage system.

Juubi Jinchuuriki

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