Wildcard

Wildcard is a young adult science fiction novel by the Chinese-American writer Marie Lu, published in 2018. It is the second half of a two-part story that began with Warcross and follows the same characters into the aftermath of the tournament.

Emika Chen is a teenage hacker and bounty hunter who entered the world's most popular online game as a player and ended up working for its creator, Hideo Tanaka. By the end of the first book she has discovered the purpose behind the algorithm he has been building, and the discovery changes what she thinks of him and of the game she grew up with.

Before she can work out what she intends to do, she is recruited by an underground organisation called the Blackcoats, which has been working against Hideo and has a different idea about how to stop him. The novel continues her search for a way out of a situation in which the available allies are compromised and the loyalties of the people around her keep shifting. Lu has said that the setting reflects her earlier work as an artist in the video-game industry.