Yes! 800 volts of pure stupid! And they paid me!!!
I used a circuit from an electric flyswatter with the addition of a bleeder resistor on the output. It’s a very simple boost converter with a transformer on it. There’s two primary windings, so the circuit gets feedback. It’s amazing what you can get in Chinatown for five dollars! The full length of the blade has metal foil tape on it, with a channel going down the middle for sparks. The tape is coupled very crudely to the circuit because at that voltage it just sparks anyway. Hit any soft part of a person and they get a nice painful zap! Probably not dangerous? Heh! Heh!