Its like this... As you know , Uchiha Madara was the mentor of Uchiha Itachi , that's why he could use Amaterasu + Susano'o , that's because Uchiha Madara teached him how to do it.
Second of all, Uchiha Sasuke got the MS through Itachi , because Itachi did a jutsu so he could've protect his brother from Danzou , that same MS that Sasuke used against Killerbee which he used Amaterasu on him , later on we find out that he can also use Susano'o , but we never saw him using the Tsukuyomi technique , the only thing that we saw him using in comparison as of Tsukuyomi is the
Genjutsu Sharingan which is no where near the Tsukuyomi of Itachi , he can do that , because Uchiha Madara himself was the one who teached Sasuke how to use the MS and his techniques , that's why those 2 can use those 2 techniques ,
Amaterasu and
Susano'o.
Third - As for Shisui , he could only use the Koto Amatsukami because it was his MS unique technique , the other 2
Amaterasu and
Susano'o he couldn't do it , because he didn't knew that those techniques existed.
As for Obito... he only used Kamui because only those who have the 2 MS (meaning , his other eye) can use the other 2 techniques , that's why Obito only used 1.
As for Madara , well... Madara has the Tsukuyomi and the Amaterasu , after all , he was the teacher of the 2 last remaining uchihas.
I think that i answered very well to your doubt
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