For a bunch of hairless apes, we've actually managed to invent some pretty incredible things.
This article focuses on a topic that exists both in the real world and in the universe of Ready Player One.

Neon Genesis Evangelion artwork
Neon Genesis Evangelion  is a Japanese animated television series (anime) produced by Tatsunoko Productions and Gainax and directed by Hideaki Anno. It was broadcast on TV Tokyo from October 1995 to March 1996.

Evangelion is an apocalyptic anime, set in a futuristic Tokyo fifteen years after a worldwide cataclysm. The story centers on Shinji Ikari, a teenage boy who is recruited by the shadowy organization NERV to pilot a giant bio-machine mecha called an Evangelion in combat against monstrous beings known as Angels. The series explores the experiences and emotions of Evangelion pilots and members of NERV as they attempt to prevent another catastrophe.

Significance in Ready Player One

Chapter 34

When fighting for Anorak's Castle, the Sixers who had obtained the Crystal Key had giant robots, some of which were Evangelion units.