<npc id="50002" displayId="30138" type="Merchant" name="Alfiva" usingServerSideName="true" title="Silver Shop" usingServerSideTitle="true">
<status attackable="false" />
<collision>
<radius normal="8" />
<height normal="24.5" />
</collision>
</npc>
npc id="50002" - custom unused id with what you call that npc.
displayId="30138" - other npc id to give it a look, for example f you want rabbit as shop, you have to use it's id
type - for example merchant, teleporter, monster and so on...
<collision> - you need to take those parametres of the npc you are cloning, in short you cant use those numbers randomly