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A few more details:
I saw it on youtube originally. I'm not actually sure what kind of swords they had, maybe they were katanas. The ending scene was something like this: the rival gangs go to fight each other on the rooftops of some city (it's a modern american city I think), all the mooks die except for the hero's brother and his best friend. Then the hero arrives and fights them with dual wield swords. And they kill him and the fight stops. There was lots of neat sword-fighting choreography.
I'll think of one later

Hello, maybe you can help me.
I'm looking for a short film I saw once but I don't remember its name. It was an action film in a modern setting. It had two rival gangs fighting each other with swords. Not samurai swords, more like european longswords. I think there was also something about two brothers, one of which had a best friend in the rival gang or something. In the end the one brother fights the other's best friend on a rooftop and they end up killing the brother that comes to stop them from killing each other.
Where else would you recommend I look? Where else can I ask?
Thanks!