Hit A Guard With A Zoomer, And He Won't Be Mad:

If you are angry for whatever reason at the Krimzon Guard, and want to make them mad and not get killed for it, then complete these steps:

1- Get a Zoomer (they're the small fast little vehicles)
2- Go full speed aiming towards a guard
3- Right before you hit him, press Triangle to mount off
4- If you do it right, the vehicle will smash into him and he will receive damage, without raising any alarms