The Mother Goose System is a device created by Sorae Igarashi in order to seal the Wretched Egg. The Mother Goose System is positioned in the center of Deadman Wonderland. It was first built in the Medical Center, but when it was destroyed by the Great Tokyo Earthquake, Deadman Wonderland was built over it.
The Mother Goose System is made out of two main parts: the Center Part and the Chorus Blocks. The Chorus Blocks are composed around the Center Part in the formation of a circle.
The Center Part transmits The Lullaby to the Wretched Egg, so its powers will be sealed. The Chorus Blocks enhance the Lullaby, making it have a broader range. When Shiro can't hear the Lullaby anymore, the Wretched Egg takes over. When the volume of the Center Part is put to maximum, the Wretched Egg is completely sealed.
Inside the Chorus Blocks, there is a dark, red liquid. In the notes of Sorae, Makina discovered that the liquid is in fact flesh from the Wretched Egg herself.
To operate the system, a key is required. Hagire Rinichirō had made many attempts to unlock the system though failed every time. Apparently, a certain Branch of Sin is necessary to unlock the system, one he didn't have access to. This Branch of Sin being Ganta Igarashi's Ganbare Gun.
Part in the story
The Mother Goose System plays a rather important part in the story. Especially because it involves the main goal of both main parties (Ganta's group and Hagire's). Ganta, the Deadmen and allies led by Makina infiltrated Deadman Wonderland to set the Mother Goose System to the maximum, in order to seal the Wretched Egg. Hagire had control over the Mother Goose System, but wanted to access its full operation so as to release the Wretched Egg. The Mother Goose System was first operated by Tsunenaga Tamaki before Hagire took over the prison.
The Mother Goose System was first seen with the Red Man confined in it, before it escaped and confronted Ganta Igarashi.
Ganta unlocked the Mother Goose System in order to set it to its maximum. But before he could, the now open and vulnerable core, made up a large piece of Shiro's old flesh, was destroyed by the Wretched Egg, completely nullifying the seal and fully releasing her powers.