... Snape? Did Voldemort ever directly kill anyone by any means other than Avada Kedavra besides directing Nagini to kill Snape?
I considered Regulus Black as a candidate, but Voldemort did not directly kill Regulus with conscious intent. Regulus discovered the existence of the Horcrux cave and technically allowed himself to be drowned by the Inferi in the lake there in order to swap out the real Horcrux for the fake one.
Is there anyone else besides Snape?