Naruto Chapter 449 - wow! I don't want to dissect the chapter like I'm preparing for a thesis presentation just take it as it is - a good one.
The technique Gedo Rinne Tensei No Jutsu just shows how powerful Pain is. He singlehandedly destroyed Konoha and killed many people. As of the moment, he is the most formidable Naruto opponent.
Well, well, some old friend of Naruto's going back to Konoha. Yup, the one he is looking for, is coming back and it won't be a HAPPY REUNION.