Ching Sen is a human potato farmer who appeared in Pitched Battle of the Great Wall Train. He mentioned his name when preparing to fight, but changed his feelings upon realizing that he was not a warrior. Characters resembling him have appeared on multiple occasions, though it is unclear whether any are actually Ching Sen.
Ching Sen is quite short, and has a round head with small circular white eyes with black pupils and a squarish body. He has charcoal coloured hair which is tied up in a small bun on top of his head, and he wears a brown coloured gown which is edged with blue on the front where it fastens and on the sleeves cuffs, and blue shoes.