Lua Scripting

Hello everyone, I’ve recently started Lua and I did this…

function Killall()
Kill (“NPC”, Eli)
Kill (“NPC”, Barney)
end
concommand.Add(“Killall”, Killall)

The bad thing is that i can’t get it to work, it says = attempting to global “Killall” at (Nil value).

Heavy: HELP!