This challenge is part of Fortnite Season 4 Week 7 Challenges and you'll have to enter the vault in Doom’s Domain. While the challenge may not seem very difficult, you'll have to know some important points.
Once in-game, head to his Domain. It's located at the northwest of the map. The city is guarded by henchmen ready to defend their leader body and soul.
Map
Be careful not to underestimate the dangers: many players will probably want to succeed in the challenge and Doom's henchmen are more dangerous than they seem. Once you have the right equipment, head north of the city. You'll face a sinister building: Doom's Cave.
On the left side of the building, under the stairs, there is a sewer hatch. Go through it and open the door on the left. You're in the bunker of Doom! At the end of the challenge, you'll gain EXP that will allow you to advance a little more in your battle pass.
Original content by Maxime "Biaggi" Ricoveri.