There is no indication that Mars Bars hates Maniac. This seems to be a misunderstanding or misinterpretation.
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In the book "Maniac Magee" by Jerry Spinelli, Mars Bars gives Jeffrey Magee the nickname "Maniac" because of his incredible feats and daring stunts.
because maybe he was black. (i mean it with love)
The person following Maniac was Mars Bars
A jerk.
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Mars Bar challenged him to a race and maniac beat him going backwards.
In the book "Maniac Magee," Mars Bars is a bully who torments and intimidates Maniac Magee throughout the story. He is a central antagonist who represents the racial tensions and division in the town of Two Mills. Mars Bars eventually comes to respect and even protect Maniac, showing a different side to his character.
Mars bars Thomson and john mcnab
Why did Maniac refuse to go home with Mars Bars
Mars Bar was surprised and disappointed that Maniac didn't rescue Russell from the East End in the book "Maniac Magee." Mars Bar had expected Maniac to intervene or stand up for his friend, Russell, but was let down by his inaction.