The Setekh Wenut is one of the Field Bosses introduced in Genshin Impact, specifically tied to the events of the Desert region of Sumeru. Here's an in-depth look.
Image via HoYoverse.
The Basics
•Appearance: Setekh Wenut resembles a colossal, mechanical scarab with intricate, glowing patterns across its body. Its design incorporates both ancient Egyptian motifs and futuristic machinery, suggesting advanced technology or ancient magics.
•Location: Desert of Hadramaveth, Sumeru: This boss can be found in the vast desert region of Sumeru, specifically in the area known as the Desert of Hadramaveth, which is accessible after unlocking certain parts of the story.
Combat Mechanics
•Phases: Engaging with Setekh Wenut involves handling its unique mechanics:
•Initial Phase: It starts protected by a sort of sandstorm barrier that must be depleted to damage its core.
•Elemental Shift: After breaking its barrier, it might shift between different elemental attacks, primarily focusing on Geo and Dendro.
•Regeneration: At certain health thresholds, it might attempt to regenerate or summon more sand solforrs, which can be interrupted for additional damage.
Attacks
•Sand Storm: Generates a localized sandstorm that reduces visibility and periodically deals Geo damage.
•Dendro Beam: Fires a powerful Dendro beam from its body that sweeps across the battlefield.
•Sand Solforrs: Summons smaller mechanical constructs that attack with Geo abilities.
•Burrow and Emerge: It can burrow underground and emerge unexpectedly, creating shockwaves.
Strategy 
•Elemental Weakness: While it uses Geo and Dendro, it's generally weak to Hydro and Electro, making reactions like Electro-Charged (Hydro + Electro) or Aggravate (Dendro + Electro) effective.
Avoiding Damage
•Use characters with high mobility or crowd control like Venti or Jean to avoid being caught in sandstorms or by its beam.
•Characters with shields, especially Zhongli, can mitigate both Geo and Dendro damage effectively.
DPS Focus
•Focus on breaking its sandstorm barrier first, then switch to high DPS characters like Eula or Hu Tao when it's vulnerable.
Elemental Reactions
•Triggering reactions can not only deal damage but also control the battlefield by exploiting its elemental states.
•Healing and Shielding: Given its mix of Geo and Dendro attacks, having a versatile healer like Diona or a shield like Noelle can be very beneficial.
Team Composition
•DPS: Characters like Keqing for Electro or Tighnari for Dendro can exploit reactions.
•Supports: Characters like Xingqiu for Hydro or Fischl for Electro to set up reactions.
•Healer: Characters like Qiqi for healing with Cryo resonance or Kokomi for Hydro application alongside healing.
•Utility: Zhongli for his shield or Sucrose for Elemental Mastery boost and crowd control.
Rewards
•Defeating Setekh Wenut grants:
•Primogems
•Hero's Wit
•Mystic Enhancement Ore
•Talent materials like "Teachings of Admonition" or higher tiers for character ascensions related to Geo or Dendro.
Tips: 
•Sandstorm Management: Stay on the move during its sandstorm phase to avoid continuous Geo damage.
•Interrupting Regeneration: Use your highest damage output when it tries to regenerate or summon, as this can prevent it from healing or adding more enemies.
•Elemental Mastery: Characters with high Elemental Mastery can benefit from the frequent elemental reactions.
•Environmental Awareness: Use the desert environment for strategic positioning, especially when avoiding its beam or shockwaves.
Setekh Wenut challenges players with its unique sandstorm mechanic and the need to adapt to its dual elemental nature, making it a memorable and engaging fight that tests both combat and environmental navigation skills in Genshin Impact.
