Friender

Friender is a brave robotic dog revived from the data of Tetsuya's pet dog Lucky. To support Casshern, Friender can transform into a jet, submarine, tank, or motorcycle, breathe flames, and stand up to the Andro Army alone.

In Casshern Sins, Friender lives with a robot community that peacefully accepts death and shows no signs of deterioration. After Casshern destroys the community while berserk, Friender follows cautiously, eventually trusts Casshern, and mainly intervenes when Casshern goes berserk.