First off, Konoha Great Tree is one of the most expensive ways to obtain him. (Yes, I bought him) I would never recommend you go through that even. Shinobi Feast, where you can buy 2 frags a day for 1600 ingots, is actually not horrible. It is guaranteed, and within a game based off of "RNG" anything guaranteed, is your friend. Second. I would tell you to save as much as you can, and wait til Christmas in a Capsule event rolls by. That was when I bought my Itachi. That event is hands down, the BEST EVENT to obtain his frags. 30k to finish him in Great Tree is hilarious..... Try more around 70-80k. I spent 15k ingots to finish my 4* Shisui. I was 11 frags away. Don't do the tree.