Tekken is a popular fighting game franchise created, developed and published by Namco. Beginning with the original Tekken in 1994, the series has seen several sequels, spin-off titles and even three films.
According to Wikipedia, the Tekken storyline typically documents the events of the King of Iron Fist Tournament, hosted by the Mishima Zaibatsu corporation. The prize? Control of the company, allowing the winner to host the next tournament.
“The piano sends a MIDI-signal, which is transferred to an Arduino,” MC Cool explained in his Vimeo description. “[Based on] the signals, the Arduino triggers transistors, which then trigger inputs on a paewang PCB (the PCB of an arcadestick). The paewang is connected to an Xbox360, [although] you can also use it on PS3.”