Crime scene investigation was an old hat for Jiang Yuan.
For an LV4 crime scene investigation, as long as the perpetrator wasn't a professional criminal, one could almost always find something.
However, upon entering the door, what Jiang Yuan first noted was the bloodstains.
His Bloodstain Analysis was at an LV5, akin to a sprinter who could run a hundred meters in under 10 seconds; from the starting motion, every action was optimized.
Though he hadn't done a detailed identification and hadn't yet conducted a thorough analysis, based on what Jiang Yuan had seen so far, he could already draw many conclusions.
For example, the bloodstains Jiang Yuan saw indicated that the murderer's movements, from the beginning to the end of the assault, were exceptionally broad.
With such extensive movements, in theory, an ordinary crime scene technician should be able to uncover some traces.