Hunter of Immortals - Chapter 23: The Third One

... a type of training method for adapters that can allow them to slowly accept prosthetic limbs, but only a small number of adapters successfully master this method. That's not because the training method is very difficult, the problem is that it's simply not worth pursuing in many cases. After all, each adapter possesses different abilities."

Having worked extensively in this field, the boss of the retrofitting shop knew more about this subject than even the teachers at the academies.