Shadow

Shadow is a mutated black furred fox from Earth. He and Foxstride underwent the same experiments perpetrated by the space aliens and were once as close as brothers, fighting many battles together for 5 years until they organized a revolt against their captors. Shado became unstable and unpredictable, causing to go down a dark path. He is now Galactic Mercenary and is Fox Foxstride's bitter rival. (You are Fox Foxstride.)