Detect player getting 115 headshots?

Game Modding | Call of Duty: Black Ops 3 | Radiant

ModmeBot:

Thread By: Frost Iceforge

I wanted to make an Origins or Gorod or Revelations challenge box, but I need to know how to detect the player doing things like getting 115 headshots on their own or spending 30,000 points or killing 3 NSZ Brutuses etc.