Ax is an Andalite from the Andalite home world. He was found by the Animorphs. He sent out dreams and Tobias and Cassie had those dreams. So the Animorphs went to the ocean and found Ax in a dome. Ax’s first morph on earth was a shark. Which he used to fight when he came out of the dome.Later Ax aquired human morph. It was a mixture between all four.

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