The Eternal Edge is an Epic Fortnite Harvesting Tool. The Eternal Edge was available via the Battle Pass during Season 23 and could be unlocked on Page 14 and costs 7 Battle Stars.
How-to Get the The Eternal Edge Harvesting Tool
The Eternal Edge is part of Season 23. If that season is still currently in the game, you can obtain this item by purchasing and/or leveling up your Battle Pass.