The Icy Crystal is one of the components needed to make a powerful Quarterstaff called Mourning Frost can be found in the Underdark.
Getting your hands on this will require a bit of exploration and a battle between not only a Drow but also the creatures that he tends to care about.
Only by obtaining the Icy Crystal along with its other parts will you be able to make Mourning Frost and it will be worth the effort.
Icy Crystal Location
You may find the Icy Crystal in the Underdark just like the other components required for making Mourning Frost but the journey can be a bit dangerous.
Located to the west of the Myconid Colony is the Sussur Tree and nearby will be a Drow named Filro the Forgotten, who holds the Icy Crystal.
How To Get Icy Crystal?
To get the Icy Crystal, you will need to defeat Filro the Forgotten as he will become hostile the moment that he or the Hook Horrors see you.
Filro the Forgotten will be on top of a cliff and you will need to climb up there while fighting your way through the Hook Horrors.
This enemy will be using spells against you but once you close in on him, you can take him out easily and loot the Icy Crystal and other items from his body.
Icy Crystal Uses
The Icy Crystal is one of three components, making it necessary to get all parts to complete Mourning Frost.
Once you have the Icy Crystal, Icy Helve, and Icy Metal, you will be able to combine these items to create the Mourning Frost.
The Mourning Frost is a quarterstaff that enhances its wielder’s Cold spells to give them more damage and the Chilled condition.
Mourning Frost also provides its user with the ability to cast Ray of Frost as a Cantrip, giving you a way to take advantage of the extra Cold damage.
Verdict
Journeying through the Underdark can be a bit difficult, which makes it important to check your surroundings instead of rushing.
Players will often encounter Filro the Forgotten as they make their way to the Sussur Tree to grab a piece of its bark for the Finish The Masterwork Weapon quest.
Filro the Forgotten is one of the three Drow mages who were on their way to find the Adamantine Forge until certain events led to him staying with the Hook Horrors.