charge down on (someone or something)
To move quickly, and perhaps aggressively, toward someone or something, The crowd gasped as the bull charged down on the matador. With the way that driver is charging down on the lead car, I think he's going to win this race!
charge down on someone or something
[for an animal or vehicle] to race or move quickly against someone or something. The angry elephant charged down on the hunters. The speeding truck charged down on the small shed.