Treasures/Memory Sphere - Previous Seasons

Overview
Memory Sphere update on 30 September (Season 13 Update):
 * Season 13 Update Transcript
 * Memory Spheres from the previous seasons are making a comeback! All Memory Spheres except the earliest classic Memory Spheres and items in S12 Essence (excluding Marks, A accessories, and B accessories) are all making their return. All Memory Spheres other than the earliest classic Memory Spheres will no longer be available for purchase. Players who own Season Memory Spheres are able to open them as usual.
 * The drop rate and guarantees for each quality grade of the "Memory Sphere: Previous Seasons" will remain the same as the previous Memory Spheres. The initial guarantees for "Memory Sphere: Previous Seasons" will inherit from the highest number of guarantees for each quality grade of the player's previous Memory Spheres. (E.g. If a player is guaranteed to receive an S item after they open a Memory Sphere 10 more times and an A or higher graded item after they open another Memory Sphere 5 more times, the player will still receive an S item after they open the new Memory Sphere 10 more times and an A or higher graded item after they open the new Memory Sphere 5 more times. Once the player receives an item of the corresponding grade, the guarantee will be reset to default, i.e. when 250 spheres are opened, an S item is guaranteed; when 60 spheres are opened, an A or higher graded item is guaranteed; when 10 spheres are opened, a B or higher graded item is guaranteed.)
 * Classic Memory Spheres can now be purchased with Clues and Inspirations. Players will not receive a duplicate A or B item until all A or B items have been obtained.
 * After "Memory Sphere: Previous Seasons" becomes available, players can set a guaranteed item once for each quality grade. Players are able to set either a costume or accessory in their desire quality grade as a guaranteed item. When they win an item in that quality grade, they will receive the item they set as the guarantee. Please set the guarantees timely as they can't be accrued.
 * The new Memory Sphere "Memory Sphere - Previous Seasons" can be purchased with 488 Clues or 96 Inspirations.
 * For the Classic Memory Spheres, players will not receive a duplicate A or B item until all A or B items have been obtained.

Memory Sphere - Previous Seasons Content List

 * Note: Items are listed according to Season in separate tables for sorting.
 * Note: Some Emotes/Standby Motions are reused in certain Seasons, the earliest documented Season of use will be noted down instead.
 * Note: Memory Spheres now no longer contain A and B Tier Rank Accessories.