Amaterasu is the highest level fire release technique,]and according to Zetsu one of the most powerful ninjutsu in existence!
when him and naruto fought at death valley. sasuke went curse mark lv 2 and used the black chidori, then naruto went to one tails and use the vermillion rasengan which cut his head band.
Amaterasu is a black flame that doesnt go out for 7 days and nights, nothing can stop it until it's time is up, has killed the intended target, or the user calls it off. This technique is used by the older Uchiha brother Itachi but during a battle he passes it on to Sasuke just before he dies. Okay if you havent exactly seen the show or read the manga i dont want to spoil the whole thing so if you want to know like the rest and all i think it'd be best if you message me, i dont know if its even possible to message on this thing but i dont want to spoil so yup! And please correct me on anything if its wrong!