This one is quite a straight forward achievement to get and is available from the very start of the game.
The quest itself can be found at the usual Board in town (Please note you may have to look under Low/High Rank to find it), from there accept it and you will automatically teleport to the Arena. This is where you will complete this task.
The Field Team Leader will instruct you on how to continue the quest, you will be swinging onto the monsters from now on like a good little cowboy!
This makes boarding the fiends so much easier than in the base game, all you need to do is hit (L2 + Circle) if you are of course on PS4, if you are not the Field Leader will tell you what to press anyway.
From now on you will be learning how to use the Claw ability, if you end up getting stuck there is a video guide blow. Each weapon used varies but it is still the same principle.
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