It is far wiser to never attack them at all. If you must, if you are backed into a corner, sell whatever weapons you planned to use and hire other humans to do it.
If you are deranged enough to attack humans make sure you get all of them, all of their genetic loci group, all of their social loci group, and make sure they don't have contracts with any formal military, informal military, or any band of seedy looking characters..
If they survive they will force themselves to be stronger and they will come and get you.
If they do not survive other humans will come and get you.