The Garden of Memories is the cemetery in Genesis. Each tombstone in the garden represents a player who was killed in the game. Because killed players do not leave corpses, the garden is used to check if a missing player has been killed in the game. Each tombstone contains the name of the deceased player, what day the player died on, and the location of the player's death.
The Garden of Memories may have been originally intended to be the location for killed players to spawn back into the game. Players reasoned that the location served no other purpose than for marking player death, therefore the garden must have served some other purpose that has been disabled in the game, such as respawning.