Then there's also OnePlus Dash charge, which looks like a USB power brick with a USB-C cable. However the phone negotiates higher voltage with special circuitry

Then there's also OnePlus Dash charge, which looks like a USB power brick with a USB-C cable. However the phone negotiates higher voltage with special circuitry in the adapter, so that kind of takes away from the 'Universal' in 'USB'. At least I now know that it might maybe work with a superspeed cable.