The principal of this Drum patch is based on triggering notes, velocity and speed. It is not that really nicely programmed but you can get the charm out of it.
For myself, I advice you to use it with scale midi from the very Ableton Midi utility effet and on a different midi track where you can route your device to it and record the midi if you wish. Random can be a nice and cosy companion before the scale actually.
You get the idea and the idea will come for sure .