UchihaFanatic
It doesn't matter that he saw the flying thunder god Jutsu he has no idea what it means the seal is meaningless unless you're a sealing master and the best sealing master at this point in time is Jiraiya and he doesn't know how to use it so it's worthless to the main character also he won't be able to use the multi shadow clone Jutsu it takes to much chakra he will only be able to make like 3 clones :/
man, your work has high potential to be above average ones. you just rushed out all foundation for development. tho technical explanation and characters development needs serious and a long thought out plans and an actual long chapters, it would be rewarding for you and me (us; readers), believe me. well, you either edit all previous chaps or just improve future chaps to be more detailed (a single long chapter that you dish out into part could work). it's a shame really, such good ideas and potential. *his one piece crossover skills could easily labeled as self made jutsu, because no one can use it other than him. a signature moves really.