Omaha is considered, by some, to be the hardest game of Poker to master. Of all of the different games of Poker, Omaha is for many the hardest to learn to play and the hardest to bluff in. It is played most often at fixed limits, like Texas Hold'em and pot limit.
With the exception of race betting, lottery and the game of Pachinko which weights almost $400 billion dollars a year, most forms of gambling are illegal under Japan's Penal Code. As such, there are no legal casinos or legal live poker rooms in Japan.