How do I trigger the (Itachi and Sasuke vs Kabuto) Boss battle?

[tengo chaleco]

Help

[SeraphinicIna]

Do this after you finished the game.

1. go to the frog Gekomatus (left from the stairwell to hokages mansion)
2. he will give you a quest to collect chakra fragments for a frog statue
3. collect the blue fragments that are all over the world, they respawn when you a area two times (best farm spot is the training grounds outside of the village, 10 are in there, just leave/enter it to let the fragments respawn)
4. when you reached 500/500 chakra points, talk to Gekomatsu again to unlock up to 5000 chakra points
4.1 (each fragment gives 20 points, so 250 fragments are needed)
5. when you reach 5000 points, talk to gekomatsu again. He will send you to the village hidden in the cloud
6. use the fast travel ninja to get there
7. when you get there, leave south and keep heading west to the area where you fought Nagato together with Itachi (beyond the area where you fought the 7 jinchuriki)
8. there will be a black fragment which will start the fragment quest
9. fight through, but be warned: the fight with madara was a joke compared to the bossfight of this one
10. celebrate your victory!

[tengo chaleco]

OMG this is going to take me the whole day lol
Thanks for the guide ! btw