Egg of Light

The Egg of Light (Japanese: ひかりのタマゴ Egg of Light), also known as the Hummingbird Egg (Japanese: ハミングバードのタマゴ Hummingbird's Egg), is an important item in Mother 3, being a crucial part of the game's plot. It is located in Osohe Castle, and is closely guarded by a variety of traps. It is implied that the Egg has the ability to restore memories, as shown in Chapter 5.

History
Duster is first sent out to retrieve it in Chapter 2 for safekeeping, as Wess senses that a crisis is about to occur in the village, and keeping the egg safe is a must. He spends much of the chapter getting through Osohe Castle to reach the Egg, and with Wess and Kumatora's help, finally reaches the castle's top floor where the Egg is located. However, another party aspires to obtain the Egg - the Pig Army. Duster manages to barely reach the Egg first, and Kumatora grabs the Egg in a panic. She unknowingly sets off a trap, and before Wess can stop her, they fall down a trap hole and land in a pit of water. Somewhere between being swept away by the water's current and escaping the castle, Duster and the Egg go missing, and are not heard from for another three years.

Later, in Chapter 5, Lucas and his party go out searching for the Egg of Light again, as Duster barely recalls hiding it in an old Clayman after losing all of his memories prior to that moment. After chasing the Clayman around the highway, they are finally able to reach it and retrieve the Egg. Upon digging the Egg out of the clay, Duster regains all of his memories.

It is later revealed that the Egg is an important object because it stores the townspeople's old memories, from before they had arrived on the island via the White Ship. The memories of the old world were to be kept firmly shut away, and had the Egg fallen into the wrong hands, the old memories would be revealed. The townspeople feared that the cycle that had destroyed their previous world would start once again, had the memories been revived, and wished to start their lives over with a peaceful village.