Below is a walkthrough for the Level 18 quest called Opening the Arena in Horizon Forbidden West. To obtain this quest, speak with Dukkah and Kalla at The Maw of the Arena near the end of The Kulrut main quest.
Gather 2 Bristleback Tusks
Bristlebacks can be found down the road north of the campfire outside of The Maw of the Arena.
Go to the Rollerback Site
Travel southeast of The Maw of the Arena to the objective in the desert.
Kill the Rollerback
Defeat the machines in the area, specifically the Rollerback.
Deliver the Machine Parts to Kalla
Head back to Kalla at The Maw of the Arena and speak with her to complete the quest.
Rewards
- 3600 XP
- 1 Skill Point