[quote=@Thundercrash]
[@my Lalia] Could you give me some examples of those would look like?
[/quote]

Well Sonya has a tazer that uses electricity and radio waves that disrupt a half-breeds powers, though if used on a human it would cause extreme pain or death. 
Bullets dipped into holy water can weaken a half-breed demons powers if the shots where not meant to kill. Also bullets dipped in demon blood will do the same thing to angel half-breed's. 

Basically I am giving you guys free rein to make stuff up. (World building) :)