Perform the following combos during Boss fights in the early parts of the game. Note: The combo will not count if you kill the Boss with it, part of it is blocked, or if the Boss is hit into a wall or off a ledge:
At the start of the game, the princess will tell you to follow her to the temple after the last combat tutorial. While following her, instead of going up the steps, continue past them. Look at the perimeter of the tree shrine in the desert. There is a small room under the shrine's roots near the edge of the cliff. Stand inside it.
To easily unlock the Assassin's view trophy, around the Martyr's Tower you'll find stairs which go to that area'sfeRtiLe grounds. Halfway up these stairs is a beam. Put the Prince and thePersian Princess on that beam.