The Nightmare Game is a month-long competition in which people with high negativity levels may participate. Every participant is called a Dreamer. Dreamers appear to others as flickering black silhouettes, and their appearances are only revealed to the person who recognizes them. The finer rules for Deamers are different every game, set by the Previsionary. Games usually take place when someone challenges the Previsionary for their spot. The challenger's identity remains anonymous to the Previsionary until the end of the game. The Previsionary and the Challenger each choose Proxies to represent themselves in the game, also unbeknownst to everyone but the one who chose them.
Before entering a game, each Dreamer must have had a recent interaction with a demon, and this usually accomplished with The Bowery cafe. Each Dreamer must then survive thirty nights or be killed in the process. Each night Dreamers must get through stages and levels, while at the same time facing their worst nightmares. The nightmares get worse as the game progresses.
Dreamers only able to stay awake for a certain amount of time each day. If a stage is completed by any Dreamer, that dreamer wakes up and can't fall asleep until the next night. The Dreamers that survived move onto the next stage. However, Dreamers can be killed by Demons or by falling off the wall.
After one month, the remaining Dreamers move on to the final stage. If only one of the Proxies survive, then the game is over and the Proxy's chooser is crowned Previsionary. All survivors of the Game are each given one wish by the Previsionary.
However, if both Proxies survive, then any extra dreamers are excused from the final stage, which involves the Proxies defeating the other, as well as the Game Master, a Demon supervising the contest.
All of the Game's staff are demons, with the exception of the Muse, who acts as an observer. The Game is run by the Previsionary. The Previsionary of the Game determines all the rules, which allow the Dreamscape to exist. As such, the Previsionary controls the entire Dreamscape's existence and composition. The Visionary works underneath the Previsionary, ensuring that the Game's course follows the rules. He is advised and served by high-rank Demon officers. One of the officers is chosen to be the Game Master for the month, whose duty is to both set the missions and ensure that as many Dreamers as possible are killed to cull the dreamer pool. Harriers work under the Game Master to erase Dreamers by summoning nightmares, while Support demons set up obstacles and provide resources for the Game.
Harrier class demons may not attack dreamers directly or assign official missions. However, if ordered to by the Visionary (or potentially the Previsionary, although she rarely interacts with Demons), Harriers may attack special targets themselves. Harriers may also act to defend themselves; if a Dreamer attacks them, then they may freely engage.
Anyone who hasn't been previously met with a demon who works in the Game are not eligible to play the Game and are considered illegal entrants if they try to.
Typically, the Game Master does not engage in the game directly until the last day (although they may act as they wish within the confines of the rules; some constantly taunt Dreamers, others remain in the shadows). The Game Master is responsible for reading Dreamer minds and assigning Boss Nightmares for the end of each stage. All Boss Nightmares appear different to every Dreamer and may be conquered by any Dreamer; all of the Dreamers with the strongest wills that are still alive at the conquering of the Boss Nightmare will benefit from this and advance to the next stage. If no Dreamer successfully conquers a stage's mission, all are killed. On the last day, the goal is always to defeat the Game Master.
In cases of extreme danger to the Dreamscape (such as a Demon defecting to the Dreamers, the presence of Taboo demons, and potentially others), the Visionary (or the Previsionary) may place the Dreamscape under Emergency Call.
The Game is watched by the Angels of the Higher Plane. The Muse, one of the Angels, is chosen to interact with the Previsionary so that he can create and give requested items to the Previsionary. He may interact freely with any participant of the Game, be they Demon or Dreamer, as long as his role as the Muse is kept secret. One key rule governing the Muse's conduct is that he may not act to change the outcome of the Game by aiding the Dreamers or Demons directly. He is free to issue advice and explanations and to provide helpful items, but he may not intervene in combat. The Muse also may not challenge a Dreamer directly to combat.
Non-Proxy dreamers who survive the game are presented with multiple options, along with one wish:
- Weak Dreamers are killed even if they win. Some may simply throw away life and choose to be killed on their own will.
- If a Dreamer has done or participated in any illegal activities in the Game, they will be killed. Special exceptions may give them penalties.
- Dreamers may become a Demon. Most are recruited under Support class, but rare cases can be recruited immediately into Harrier.
- Dreamers may extend their life, with the side option to never participate in such severe nightmares again. This is considered unusual. However, the Angels don't consider it to be a loss. The Dreamer's art and imagination will find its way into his or her culture and increase the overall imagination of the population.
- The absolute best of the Dreamers are given the honor of ascending into the Higher Plane. Demons may also ascend to the rank of Angel, although exactly how they are chosen remains a secret.
The Previsionary is the sole determinant of a Dreamer's fate; she bases her decision on how the Dreamer performed during the week. The Demons score Dreamers on various attributes (stages accomplished, lower-level demons defeated, and among others), and these scores are a measure of the Dreamer's performance. Although rare, Dreamers who have been killed may be restored to life. In these cases, the losing Dreamer forever loses whatever is dearest to them in order to participate. It can be physical, such as mementos or people, or more physical or immaterial such as one's appearance, dreams, or memories.