Stone Brain

The Stone Brain was a living artifact, created by the Sages of Lat-Nam in the hopes to stop the Brothers' War on Dominaria. The Brain had the power to stop wizards from using magic.

History
Gull and Greensleeves first saw the artifact as a falling star descending upon the Whispering Woods. The wizard Towser retrieved it with their help, believing it was a Mana Vault. After he tried to absorb Greensleeves' power with it, they ended up fighting each other.

Thanks to an incident with a student of magic, it was revealed to Gull and Greensleeves how the Stone Brain, which had taken the form of an helmet, worked: once worn, thousand voices (the voices of the Sages of Lat-Nam) order the wizard to stop using magic, or face madness. Within the artifact are also hidden all the spells known by the Sages. A test was conducted on Haakon, and he became a sort of slave to Greensleeves, just like the creatures summoned by other wizards. Gull confronted Greensleeves about using the Stone Brain, but she was convinced this was the only way to stop the evil wizards.

Haakon managed to free himself from the Stone Brain command just enough to summon some Phyrexian Gremlins, who snatched the artifact and returned to their home plane. After Greensleeves planeswalked to the Stone Brain she found out that she could resist the voices, as they were similar to the effect of the Whispering Woods.

Days later, they find out that Dacian the Red, the wizard who once battled with Towser over White Ridge, is at the site of the crater where the Stone Brain had fallen from the sky. The army captures Dacian and puts the helmet on the wizard. Greensleeves resolves to let Dacian and Haakon go. Unbeknownst to Greensleeves, those tagged by the brain can contact one another, so Dacian and Haakon form a truce and seek out other wizards, Karli and Towser, in order to form an alliance and stop Gull and Greensleeves' crusade.

When Greensleeves finally understands that the evil wizards have find one another thanks to the Stone Brain, she intends to discover every secret of the artifact. She dons the helmet and finds out that its ultimate secret is buried somewhere in the ruins of the College of Lat-Nam, in the long lost isle of Lat-Nam.

On Lat-Nam, the party discovers a skull of a Sage, to which she asks the secret of the Stone Brain. Using the secret of the helmet revealed to her by the skull, Greensleeves uses the Stone Brain to strip Towser of his magic. Seeing how the punishment causes Towser to run away, screaming madly, Gull finds the solution too drastic and cruel, so he decides to let the other wizards retain their magic, but only for doing good. Greensleeves keeps to herself the last secret of the Stone Brain, its ability to give magic to anyone, thinking that a similar power is sure to cause another war for control over it.