In the world of my own design, demons employ endless methods against humans.
There are numerous ways to replace a person; Mister Hua Pi used a human skin puppet, the Insect Demon implanted itself in the brain to control the body, and then there are even more mystical methods, like Ali, who directly replaces your memories, making you believe they are whoever they wish to be, or like the monsters from the Path of Yin and Yang, who by devouring your soul's memories, can shapeshift into your appearance.
And each demon requires a different strategy to deal with.
To strike accurately and effectively, the best method is still to find the demon's weak point and set a trap based on one's understanding of demons.
But what exactly is the opponent?