Permission Granted
Defeat the betrayers within two and a half minutes.

This is the first battle in the Shadowlord's castle, you can probably guess who it is, but i wont spoil it. Skip all cutscenes, don't worry if you miss this trophy in your first playthrough, it will be much easier to obtain in New Game+

Hit either of the two targets with Dark Hand and slash with your sword before they can teleport away for extra damage, repeat a few times and a cutscene will play. After the cutscene they can use all of your powers. Repeat the same process as before while blocking their magical attacks. Once their health is almost completely depleted, they will teleport to the center of the room and you will be treated to another cutscene. If you managed it within the time limit, the trophy will unlock.