Click heads of Maggio and read what crit to kill by name. Go to Desert Town and find named crit. Go outside town and gather a zoo and drag them in to the named crit. Hang around on crit so zoo eventually kills the crit. Search for ring and hold in right hand and click the heads of Maggio. He swears that he will never gamble again and gives you a Black Pearl. Trade Black Pearl for Infravision Helm in Timmy Cave.
The benefit of the helm you can get from Giant's keep is that not only does it provide combat stun prot, but you can also pad it with yeti fur and get combat adds of 4, which is not available from a nork IV helm.