"So under Pier Nine, the Huo Family conducted those experiments and forced Li Zhengyuan to identify the tattoos, in order to find the right one that could be used to enter the Underground City?" Guan Chen asked in surprise.
Lin Wu nodded, "Li Zhengyuan said he didn't know, only that female team member had been near the Underground City. And the Huo Family learned how to make the tattoos by coercing Shi Ying. However, he was quite cunning and didn't tell the Huo Family everything—just knowing how to make the tattoos isn't enough. You also need a special ingredient; it's the substance hidden within the tattoo that becomes visible."
"Determining whether a tattoo is real and usable is simple, it just needs to react with this ingredient. But the Huo Family didn't know that, they thought since Li Zhengyuan survived, he must surely know how to identify the tattoos, so they imprisoned him."
