Board Thread:Boruto Discussions/@comment-43689784-20200520151938/@comment-44914736-20200530020545

Jason of the Mangekyou wrote: Adding Dark swamp to this guy's arsenal is a huge Jiraiya indicator.

The huge indicators were actually several chapters back with Koji Kashin knowing the Rasengan and Summoning Frogs. You need to sign a summoning contract to summon frogs which you can't explain some unknown enemy summoning frogs without it being Jiraiya or most likely a clone with no memories of his past but retaining his fighting ability and jutsu which also explains the rasengan. Its been established you can't copy the rasengan and I'm pretty sure Naruto, Kakashi and Konohamaru would remember teaching such a technique to someone like Koji Kashin. You can't copy the summoning technique either so same rule of deduction applies. Its definitley a clone of Jiraiya that was created with a blood(and or) chakra sample that was probably secretly enhanced with Shinobi Ware like the other Inner members of Kara by Amado