Rashomon and Hero share only one point in common: In both movies, there's a certain story that's being told from different angles which means that only one story have many versions. Other than than, everything else is dissimilar.
“Rashomon” is the most famous film to tell the same story from multiple perspectives. Though “Monster” is closer in its cynicism and absence of a conclusive answer to the source short stories “Rashômon” and “In a Grove” by Akutagawa Ryûnosuke.
Both movies are based on classic jidaigeki novels by Akutagawa Ryunosuke..................................................................................................................................................................