Peerless Cross-Domain Medical Immortal

In his previous life, the 'Plague God' of the celestial realm, Gu Yan Mu Chan, was ambushed and his soul transmigrated to Earth. When he woke up, he was a poor medical school dropout who couldn't even afford next month's rent. But he soon discovered that the oldest life forms on Earth are not humans, but the invisible microorganisms. Over billions of years of evolution, they have built a sophisticated system far beyond the celestial realm's understanding. While others practice medicine by observing, listening, questioning, and taking pulses, he opens his 'immortal sense' and directly communicates with bacteria. While others use drugs to kill bacteria, he holds 'meetings' with viruses and negotiates terms. Stomach problems? Helicobacter pylori is just throwing a tantrum; soothe it and it's fine. Cancer? That's a cellular-level microbial imbalance; rearrange the 'battle formation' and it can be reversed. In his hands, difficult and miscellaneous diseases are merely 'neighborhood disputes' in the microbial world. With the system in hand, skills are earned by grinding. Early upgrades are like riding a rocket, but later levels? Sorry, you'll have to search the world for opportunities. Yet, as he thrives on Earth, the aura of the 'Super Bacteriophage Immortal' that ambushed him in his previous life quietly emerges in the depths of the city... He heals humans, ghosts, and immortals; to cross domains, one must first cross microorganisms. — Description from novelcodex.org