Fairy Tail Zero is a manga written and illustrated by Hiro Mashima. Fairy Tail Zero is a spin-off of Fairy Tail and is about the story behind the creation of the Mage Guild Fairy Tail.

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Fairy Tail Zero (フェアリーテイル ゼロ, Fearī Teiru Zero, romanized as FAIRY TAIL ZERØ in Japan) is a Japanese manga series by Hiro Mashima and a spin-off of his manga series Fairy Tail.

The story behind the creation of Mage Guild Fairy Tail begins to unfold on Tenrou Island. On the year X679, Mavis Vermilion is left to fend for herself after a war takes the lives of those who reside on the island. Seven years later, she encounters those who will, in the near future, title themselves as the founding members of Fairy Tail.

For more information, see the Fairy Tail Wikipedia page, or the Fairy Tail wiki.