The kill alias is if not the, at least one of the most important and frequently used aliases you'll have.
A good kill alias should keep you from attacking playerkillers, NPCs that will get you killed or losing inventory such as cats, priests and contractor NPCs in Djelibeybi, hags in Bes Pelargic and stone palms in the oasis as well as contractable NPCs and quest NPCs.
The first thing you got to decide when writing a kill alias is whether it should be exclusive or inclusive, what not to attack or what to attack.
The following is an example of an exclusive kill alias, please feel free to add to it.
kill all except Hin-lop-heds&Kang Wu&Lap-lip&Lip-phon Lap-top&Mihk-gran-bohp&Noc-noc-bang&Phin-lip&Phos-phor&Pkara Stainmaster&Ptarquet Shazam&Ptyler Stonecutter&Sandy Ptate&Tag-ahn-ruhn&Ut-lat-khin&Yclept&bats&cats&fireflies&hags&killers&lights&moths&pets&priestesses&priests&receptionist&shady man&sheep shearers&shopkeepers&stone palms&summons