Vendor Safe spell

[starving030]

I have a vendor that I want to cast a spell to who ever comes near them but stops when you run away. How would I do that in mangos?

Its a spell that causes the player to not be able to attack anyone. its gonna be a safe spot npc that actually sells stuff. the spell is [serentiy] and it is used on retail for exactly the same thing on a quest. The NPC on retail I think gives it off like an aura. I was gonna try to use it in AI agent tables butmangos is different and i dont think thats gonna work this time. maybe if you come in its gossip radius or some way the npc can give off the aura. I dont know quite how to make it work.