In 1970, Masahiro Mori proposed the uncanny valley concept. At the time, the proposal aroused little reaction, However, the uncanny valley is just a hypothesis, not a strict theory. Many subsequent studies have shown that it is true that the uncanny valley is reasonable; With the development of game consoles and personal computers, uncanny valley in video games will become more and more common. but, for the time being, special introductions and game related research on the uncanny valley are still very rare. In this paper, with Masahiro Mori’s uncanny valley as a benchmark and using the evolution of Tomb Raider’s Lara Croft over 20 years as an example, we analyze the significance of the uncanny valley in the design of realistic adventure game characters from such aspects as facial expression and texture. It's not easy to see the development of the technology in the game by using this approach. And it makes game makers determinate the scope of uncanny valley more exactly to made better games.