Heal Life On Attack

[GOD Esteve]

Hello guys

Im trying to make a item that will add life when player attack about 30% of damage.

<event type="statschange" name="ItemRegen" script="MEUS/itemregen.lua"/>

registerCreatureEvent(cid, "ItemRegen")

function onStatsChange(cid, attacker, type, combat, value)
if isCreature(attacker) == true then
if(getPlayerSlotItem(attacker, 3).itemid == 12685) then
dmg = math.ceil(value*(30/100))
doCreatureAddHealth(attacker, dmg)
end
end
return TRUE
end

Work only with player
When hit a monster don`t heal

Please somebody help to fix