The ice sword was used during the 2007 Christmas Event to make a Snow warrior.
This un-equipable weapon looks similar to a Dragon two-handed sword prior to its graphical update, except that the sword is a translucent blue rather than red.
After it is obtained, the players may not take it out of the Land of Snow. If this is attempted, the sword will automatically disappear. This item could be used on a snowman which you could create to battle other snowmen in the Land of Snow. These warriors could be healed by snow being used on them. All of the snow men are the same combat level, so the combat triangle must be used to win a battle, along with the tactic of using snow to heal.
This item is sometimes mixed up with the icicle sword, a non-existent item which came 3rd in the guaranteed content poll for Christmas 2008.