God of Gamblers

Do San (the God of gamblers) is a legendary gambler helped by his supernatural abilities. He undertakes to help a friend pay a debt by beating his friend's advisory at the card table. Despite being assigned a bodyguard, Do San has a freak accident, which leaves him with partial memory loss and at the mental stage of a child. The small-time hustler Knife, his side-kick, and his girlfriend, responsible for the accident, takes care of the mentally disabled Do San. After some time, they discover that he has not lost all of his powers and take him on a round at the local gambling halls. After being chased by both Knife's loan shark and enemies closer to the home of Do San, a final showdown at the card tables may take place.
(Source: Staale A. Olsen at MDL)