UPDATE 11/12/18: Today’s patch notes confirm the Infinity Blade will indeed be a one-off weapon available every match from the newly-opened up Polar Peak, the Ice King’s lair. Just one player will be able to wield the sword at any time, just as Fortnite’s Thanos event featured the Infinity Gauntlet earlier in the year.
Sword slashes will deal 75 damage, while the weapon’s alternate fire will allow you to leap large distances and destroy objects, with a smaller 25 damage upon landing. Anyone wielding the sword will gain 200 health and shield and constant regeneration. If they are defeated, the sword will drop for others to pick up instead.
Patch 7.01, which introduces all of this, is available to download now.