(ênfase é minha)
The Wind Singer is a young adult novel written by William Nicholson. It is the first book of the Wind On Fire Trilogy. It follows the quest of twins Kestrel and Bowman Hath, and their friend Mumpo to restore the "Voice of the Wind Singer" to their city and bring happiness to their cruel society.
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The book begins in the walled city of Aramanth, an extreme meritocracy where endless exams and ratings are the only way to move forward to improved life stations; to be unsuccessful in this is seen as a great source of shame.
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Using an archaic map given to her by the Emperor [Kestrel] sets off, joined by her twin brother, Bowman, and their brave but pitiful new friend, Mumpo, who has an unshakeable affection for Kestrel. They meet a variety of tribes and individuals including the fearsome nomadic clans of Ombaraka and Omchaka.