what if this is why BZ could modify the content of the tablet....

[Alfred Pennyworth]

when hagoromo was dead/nearly dead BZ took control of his corpse/body and did the modification.

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or he could've done the same with a regular sharingan user if the content can be accessed by 1-3T sharingans

(it's more likely that the additional text by BZ is actually accessible to low-level dojutsu...otherwise how would the majority of uchiha's be tricked and manipulated ? MS were already rare...let alone EMS or rinnegan)

it's unlikely yet feasible isn't it

 

[Goetia]

Maybe he just did it when Hagoromo wasn't looking?

 

[monsoonfox]

How black zetsu can modify it he don't even have sharingan to read what is written in it ?

 

[Alfred Pennyworth]

Maybe he just did it when Hagoromo wasn't looking?

BZ might have needed advanced dojutsu to accomplish the task....

How black zetsu can modify it he don't even have sharingan to read what is written in it ?

hagoromo's rinnegan was a fitting tool

 

[ministerC4]

Hand writing isnt based on your body, its based on the choices you take when doing your letters.
its based on your style, and it can for one be taken much easier than taking someones body, itachi copied shisui's hand writing and no one could tell the difference remember?

 

[jerry2255]

maybe BZ tricked indra to change d writing

 

[Alfred Pennyworth]

Hand writing isnt based on your body, its based on the choices you take when doing your letters.
its based on your style, and it can for one be taken much easier than taking someones body, itachi copied shisui's hand writing and no one could tell the difference remember?

it's not about the handwriting....
the fuss with BZ's modifying the tablet revolves around why he managed despite not possessing adequate dojutsus to decipher the tablet itself

 

[Hiraishin Stage 3]

Black zetsu obviously has some ocular powers being born from kaguya, he also has been "recording" events ever since the beginning of part two
Once he could see what is in the tablet, modifying it in the same style of writing would be easy

 

[Angelic.]

what exactly is the language written? space rabbit or is it some kind of code? maybe kaguya could read it fine, taught bz her baby how to and also hago. like kids knowing their parents. :| im just messing..

 

[ministerC4]

it's not about the handwriting....
the fuss with BZ's modifying the tablet revolves around why he managed despite not possessing adequate dojutsus to decipher the tablet itself

BZ is the spawn of the same person who gave birth to the sage, I'm 100% sure BZ has the prowess that allows the sage and the uchiha to read the tablet, Hell the sage doesnt even have a sharingan lel.

 

[Beauty Busty Beast]

You might be right, it make sense.
He definitely used someones body, that's for sure.

 

[NineSNS]

Black Zetsu is not a typical ninja or human for that matter. If he can split his body, attach it to people and take control of them, he is not bound by the same "rules" that everyone else is. Altering the tablet shouldn't be a problem for him given all his other weird attributes.

 

[Zol]

Well, we don't know why it is difficult to read the tablet to begin with. If it has something to do with the language itself, Kuro may know it since he is Kaguya's will.

Also, Kuro is a very special being, he is no human, he doesn't actually "live" (no aging, metabolism etc.), he can somehow "record" things, attach himself, or rather itself to beings...I don't find it farfetched he can understand and tamper with the tablet.