Crossing Two Realms, I Can Become Stronger by Killing Enemies

After accidentally acquiring the system, Chen Da was able to continuously travel to other worlds. [The first world, the lonely city of Tang Dynasty. When the smoke rises, no one can return, and the lonely city builds heroic souls. [The second world, Jinling in the 1930s. With the sound of gunfire, people have no regrets, and the bloody city turns into heroes. [The third world, the world of dogs. When the barking sounds, something strange happens, the animal path is originally inhumane] [The fourth world, the world of martial arts Say "good wine" and "brother", and a knife in the back will make you crazy] [The fifth world, the fantasy world. I'm sorry for being a human being. If you bully others, I'll be indebted to you. The sixth world… After traveling infinitely, I suddenly looked back. Chen Da discovered that——Invincible is so lonely! ! !