One of the challenges in the Fortnite Ice Storm event is to deal 5,000 damage to The Ice Legion by using explosive damage. Many players have wondered exactly who or what The Ice Legion is, and you're about to find out just that, as well as how to complete the challenge.
The Ice Legion consists of three enemies; Ice Brutes that a big enemies, the high and skinny Ice Wraiths, and the zombie-like Ice Fiends. You can deal explosive damage to either of these three enemies to gain progress towards the Ice Storm Challenge.
All of The Ice Legion enemies can spawn at random places all around the map, so you don't really need to go anywhere specific to grind them. Simply equip weapons that deal explosive damage (such as the grenade launcher, the rocket launcher, the quad launcher, grenades and dynamite), find a squad, and just roam the map and kill as many Ice monsters as possible with the explosive weapons. It's of course also possible to do this solo, but it will likely attract enemy players to your location.
There is also another challenge that requires you do kill 250 Ice Fiends, and these two challenges can actually be done at the same time if you kill the Ice Fiends with an explosive weapon. You are likely to get the 250 kills challenge done first tough, so make sure to deal some explosive damage to the other Ice enemies as well.
As said above, you need to deal a total of 5,000 damage to The Ice Legion, but you got a total of two weeks to do it, so it should not really be difficult at all. When you finish the challenge, you get awarded with 500 XP.