Nevada is one of the 50 states comprising the United States of America and a recurring location in the Zero Escape universe. As a location, it first appears in Zero Escape: Nine Hours, Nine Persons, Nine Doors, and is where the events of both that game and Zero Escape: Zero Time Dilemma take place. It is known to contain Building Q, the Mars Mission Test Site and the Underground Shelter.
At some point before 2018, Building Q was built in the Nevada desert. It was either built or purchased by Cradle Pharmaceutical, which then used it for the First Nonary Game, where 9 children were forced to play the Nonary Game and transmit puzzle answers to their siblings in the Gigantic. The building was abandoned afterwards. Crash Keys later came in and renovated it for the Second Nonary Game.
Nine Hours, Nine Persons, Nine Doors
On November 1st, 2027, the Second Nonary Game was held in Building Q. The players, however, were unaware of their true location until they exited Building Q and saw that they were surrounded by a desert -- up until that point they had believed that they were imprisoned in a sinking ship. They drove away using a car that Akane and Aoi left for them. During their drive, they found and picked up Alice, bringing her out of the desert with them.
Virtue's Last Reward
Nevada was only briefly mentioned during Virtue's Last Reward. It was mentioned by Alice and Clover in Alice END and Clover END respectively, when the end and aftermath of Nine Hours, Nine Persons, Nine Doors is addressed. It was brought up in Tenmyouji END and Phi END as well. Also, the events of Zero Time Dilemma are lightly discussed in these ends.
Zero Time Dilemma
On December 25th, 2028, a mission to simulate life on Mars is held at the Mars Mission Test Site. However, Free the Soul releases Radical-6 into the facility, so Akane sends Sigma and Phi to infiltrate the test site and stop the virus from escaping.