Shadow Warrior (2013)

Shadow Warrior 2013 is a reboot of 1997 game with the same name on it, Shadow Warrior. Setup is pretty simple - Lo Wang, our protagonist in a very specific quest. He is a hired assassin with a mission. He has to buy a very ancient katana with powers to kill immortals. When arrives at the place of the deal, everything turns in quite a disaster. Demons attack and slay everything in its path and Lo Wang decides to cooperate with them in order to bound three swords into one, making this very old and ancient katana a real and unstoppable force.