The first thing that players will need to get the Cyborg Spec in Project Star is 8500 cash. How you get this cash is up to you, but you will need it to start the process. You will also need to ensure that you do not have any fighting style equipped.
After that, head out into the Great Desert and travel along a trench in the sand that moves between an old truck and a castle structure. Eventually, you will find a large hole in the ground surround by some broken and twisted metal. Go down inside it to find an old German scientist who will give you access to the quest to get Cyborg combat if you give him the 8500 cash.
He will give you a quest called Cyborg Transformation that you can complete by running the dungeon behind the green door in his room. The dungeon itself is not hugely difficult to complete, and you should be able to farm it on a high difficulty level.
Once you have ran the dungeon enough time to get all the parts you need for the Cyborg Transformation, it will automatically give you access to the Cyborg Spec combat style, which you can access in the Skill Tree.