This was not due to carelessness on Sasuke's part, nor had his mastery of genjutsu declined.
Just seconds before Sasuke burned the talisman, he had been subjected to a simultaneous, saturated assault by Orochimaru, Kabuto, and the Sound Four.
All manner of genjutsu, ninjutsu, secret techniques, and hidden weapons had come sweeping toward him. Any ordinary shinobi would have met their doom here long ago.
Chapter 185