Cloister of Trials
From Final Fantasy Wiki
The Cloister of Trials is a feature of the Temples of Yevon in the game Final Fantasy X. Each Cloister is a large puzzle which players solve in order to advance to the Chamber of the Fayth. Solving a Cloister involves such actions as pushing moving pedestals, removing or replacing a variety of Spheres (each temple has a sphere named after it, while all temples have Glyph and Destruction spheres), or strategically activating or deactivating moving elements of the Cloister's structure. No battles occur while characters are within the Cloister. After each Cloister of Trials, the summoner Yuna obtains a new Aeon.
Cloisters of Trials are present in Besaid Temple, Kilika Temple, Djose Temple, Bevelle Temple, Macalania Temple, and Zanarkand. They are not present in the Cavern of the Stolen Fayth, Remiem Temple, or Baaj Temple.
You can unlock the Aeon Anima by obtaining all the secret chests that are revealed by Destruction Spheres, with the exception of Bevelle, in which you obtain the item right before the Chamber of the Fayth (due to the fact that you won't be able to enter the temple again).
Only summoners and their guardians are permitted to enter the Cloisters of Trials; as evidenced to Wakka's dialogue to Tidus at Kilika, the summoner himself/herself will get into trouble if any non-guardians accompany them.
Two years into the Eternal Calm, the Cloisters of Trials have been rendered off-limits to everyone.
