Start with a Blast, Start Strong from Eavesdropping

(This is a story that takes place in a parallel world similar to Earth. It is not a time-travel, non-rebirth, and non-systematic story. Any similarity is purely coincidental.) Xie Rushan, who grew up in a welfare institution, picked up a silver-white round block on the beach - a brain wave decoder. As a result, he gained the ability to interpret other people's brain waves, eavesdropped on the secrets of other people's brains, and used these secrets to develop and strengthen himself. Eavesdropping again and again, punishing the bad guys again and again, his body gradually changed...