This article is arranged to reflect the Ender timeline. However, the Ender Quartet: Speaker for the Dead (1986), Xenocide (1990), and Children of the Mind (1994) was written first; then Ender's Shadow (1999), First Meetings (2004), and Shadow of the Giant (2005).
The student picks a character and goes through a number of situations. One such situation is the Giant's Drink, in which the Giant offers the player a choice between two beverages, claiming the correct choice will take the player to "Fairyland;" however, the choice is a no-win situation in that there is no Fairyland and no matter which drink the player chooses, consumption causes the player character's death. This scenario is designed to measure how suicidal the student is (not an idle concern, as at least one Battle School student has successfully killed himself). Ender repeatedly plays the situation out, causing concern among the teachers. On his last attempt, however, he kicks the drinks over and claws into the Giant's eye, killing it and becoming the first student to ever enter Fairyland. The Game manages to create a Fairyland as it goes along, tailoring it specifically to the personality of Ender Wiggin.
In Ender's Shadow, the Fantasy Game is discussed in greater depth. It is described by the teachers themselves as an extremely complex program that generates content procedurally. The Mind Game is never meant to be conclusive; it only makes connections and discovers patterns that are too subtle for the human eye.
In Shadow of the Giant, when Bean suspects Peter Wiggin of embezzling Ender's trust fund for his Hegemony uses, he requests that Ender's trust fund be placed under automatic control of a computer program. The Mind Game is modified to predict markets and invest Ender's trust fund appropriately, which it proves alarmingly good at; it is also used to review demographic data and help Bean find seven of his eight stolen embryos/children. It is assumed to have grown in complexity during the 3000-year gap between Shadow of the Giant and Speaker for the Dead, especially as Graff describes the Mind Game as being able to reprogram itself, and finally becomes the sentient Jane.
An electronic "jewel" in Ender's ear allows both of them to communicate and for her to see and hear everything from Ender's vantage point. She helps Ender with many things. For example, in the very beginning, she contacts an orbiting ship and pays $40 billion for it and the cargo. Ender's reliance on Jane becomes obvious when she no longer helps him; he must ask Olhado to help him with his finances but Ender doesn't even know what his own password is.
Jane plays a pivotal role in the development of the book. Jane guides Ender to Lusitania and helps him out considerably in obtaining information. When Ender disconnects her (turns the jewel off), she realizes that Ender does not need her as much as she depends on him. She reconfigures herself to no longer be so focused on Andrew Wiggin. Concluding that Ender needs a common enemy to unite all of Lusitania together to help the piggies, she runs analysis on data and subvertly gets Starways Congress to order the destruction of the planet. She makes it appear as Lusitania has cut off their ansible (she did this mainly to save a xenologer from being killed), triggering Starways Congress to send the "Evacuation Fleet," which is actually carrying the Little Doctor to destroy the planet. With the threat, Ender unites the colony to form a treaty with the piggies to assure mutual cooperation and peaceful coexistence.
No longer attached to Ender, she bonds with Miro, Ender's paralyzed stepson who was the xenologer who was almost killed earlier.
Facing defeat, Jane reveals herself to Qing-Jao and Si Wang-Mu. After a heated discussion, Qing-Jao despairs because Jane's power is vast: Jane can shut down all the ansibles, making it impossible for Qing-Jao to reveal Jane's presence. However, Jane knows that she cannot continue to silence Qing-Jao's message forever, since it would snowball into cutting off the entire planet of Path. Thus, Jane refuses to silence the ansible, Qing-Jao sends the message, and Starways Congress orders the silencing of all ansibles to kill Jane.
In this book it is revealed that the Hive Queens, who were seeking a way to contact Ender during his crusade, attempted to construct a philotic 'bridge' based upon those connections. Jane was the bridge they constructed, and in order to make it live, they imbued it with that quality which all living things have: a philote. Jane, in other words, is an actual lifeform, not just a collection of software. The Hive Queen further explains that Jane's philote was called from a space outside of the universe, just as all philotes are. Grego and Olhado, hearing this, hypothesize that, if someone can somehow contain all the information on how a spaceship's philotes are organized (i.e., its structure down to a subatomic level), that person could essentially will the spaceship Outside and Inside again. This will be entirely dependent on Jane, since no one else has any chance at holding or even learning all that information.
Jane's test flight consists of a box with a door (technically a spaceship), Ender (to whom Jane is inextricably philotically linked), Miro (for the same reason), and Ela (so that she can create the recolada virus once they are Outside). It is a success: Ela manages to envision and thus create the new virus, and also a new virus to give to the people of Path, to undo their genetic tampering and spread the increased intelligence across the world. But others are busy creating as well. Miro, by going Outside, creates a new body to replace his crippled one. And Ender accidentally manages to create copies, almost caricatures, of his siblings Peter and Valentine.
Jane is also simultaneously responsible for instantaneous travel anywhere in the universe. A simple spacecraft is constructed (later deemed unnecessary due to Jane's precision in transportation), and through holding the image of the traveler in her consciousness, Jane can pick up the image and place it anywhere in the universe instantly. This advancement is threatened by Congress' attempt to deactivate her "program."
In the end, Jane is given corporeal form in the body created in the form of young Valentine, comprised of a portion of Ender's aiúa. Jane's aiúa is capable of transcending this corporeal form and returning to the philotic link of the mothertrees, or the reconstructed ansible network of which she was born, thus preserving the instantaneous method of travel. This new Jane/Valentine hybrid marries Miro, in a double wedding ceremony along with Peter and Si-Wang-Mu.