The ice shield was created many moons ago by a hero trying his hands at some simple weapon making but they don't seem to have thought it through. A hero using it is unable to leave the freezing cold environment around Trollbridge or it melts soon afterwards. The shield is also very brittle and the very opposite of shatter-proof. The main advantage of using this otherwise rubbish piece of equipment is that it's shape lends itself to being hurled at the opponent so that it then sticks to them. They soon find that lugging a heavy piece of ice around isn't the best fighting strategy and soon give up.
Some variants of this shield are a little more useful as they often have basic magical protection, but they still melt since the wizards are too absent-minded to remember this weakness of the shield. It should also be noted that the bipolar bear is rather fond of this shield's taste which is often useful.