For this trophy you'll have to pull of a 50-hit combo or higher during battle.
Now this trophy can be easily earned with a buddy. Just enter VS Battle, under Free Battle Mode. Then when choosing a character pick either Neji or Hinata Hyuga as your main character. Once the match starts approach your friends and press Y then B and they will perform their 64 Palms Rotation, or 64 Palms Guard respectively, depending on who you chose.
The results will produce a 64-hit combo!