Complete 5 swings in a row to the same direction with the grappling hook.
Silver Trophy
Thanks to Vitten this is the easiest location to complete this trophy.

Level 11 , Ruins of the Perished.

At the end of the level you will find a bridge above some lava. Use the bottom of this bridge to complete this challenge. It is recommended to place some planks below in case your Thief falls, now just swing forward 5 times hitting only R2 or square DO NOT JUMP IN BETWEEN SWINGS

Alternate Method