Here's a detailed guide for The Lost Valley Domain in "Genshin Impact":
Domain Information:
•Location: In The Chasm, specifically in the Fuao Vale area of Liyue.
•Type: Domain of Blessing, focused on providing Artifact Sets.
How to Unlock:
•Adventure Rank: Requires Adventure Rank 40 to unlock.
Unlocking Puzzle:
•Geo Puzzle:
•Step 1: Find the domain entrance, which is initially blocked by a large rock with a Geo symbol.
•Step 2: Locate a pressure plate near the domain entrance (south of it), where you'll place a Geo Construct (using characters like Geo Traveler, Zhongli, or Ningguang).
•Step 3: After placing the Geo Construct, a wind current will appear; follow it to a glowing Geo rock pillar.
•Step 4: Hit this rock pillar with a Geo attack to create a resonance that will break the rock blocking the domain entrance.
Enemies:
Primary Enemies:
•Ruin Guards - Mechanized enemies with strong ranged and melee attacks.
•Ruin Defenders - Similar to Ruin Guards but faster and with additional attacks.
•Ruin Destroyers - Larger, tougher versions with more health and capable of flying.
•Ruin Scouts - Smaller, quicker with burst damage capabilities.
Domain Step-by-Step Walkthrough: 
Preparation:
•Assemble a team with strong shield capabilities since Ruin enemies have high damage output. Characters with good burst damage are also crucial for breaking enemy cores.
Levels:
•Levels I - IV: Each level increases in difficulty:
•Levels I - II: Lower level Ruin Guards and Defenders, manageable with basic strategies.
•Level III: Introduction of Ruin Destroyers, requiring more strategic play.
•Level IV: The toughest, with a mix of all Ruin types, including Scouts, demanding precise timing and strong team synergy.
Ley Line Disorder:
•Ley Line Disorder: Using Elemental Skills unleashes a shockwave that deals True Damage to nearby enemies, promoting frequent use of Elemental Skills.
Rewards Schedule:
Artifact Sets:
•Echoes of an Offering - Increases Normal Attack DMG through a luck-based mechanic.
•Vermillion Hereafter - Boosts ATK after using Elemental Burst, especially beneficial for characters who lose HP in combat.
•Other Rewards: Mora, Adventure EXP, and Companionship EXP. Collecting rewards requires 20 Original Resin.
5 Strategies for The Lost Valley: 
•Shield Priority: Shielding is key; it not only protects but also triggers the Ley Line Disorder's shockwave.
•Elemental Skill Focus: Characters with low cooldown on Elemental Skills like Fischl or Xingqiu are ideal.
•Burst Management: Time your Elemental Bursts for when Ruin enemies are vulnerable or grouped.
•Crowd Control: Use Anemo to group or stagger Ruin enemies, making them easier targets for your team.
•Elemental Reactions: Use reactions like Overload to deal extra damage or Electro-Charged to control enemy movement.
5 Tips for The Lost Valley: 
•Know Your Ruins: Each Ruin type has unique attack patterns; learn them to anticipate and dodge effectively.
•Positioning: Stay mobile to avoid being cornered by Ruin enemies' ranged attacks.
•Artifact Set Utilization: Even if not farming for specific characters, understand how each set benefits different playstyles.
•Save for Level IV: If possible, go straight to Level IV for better artifact drops but be prepared for a challenge.
•Healing: Keep a healer or use healing food; Ruin enemies can deal significant damage over time.
Ley Line Disorder:
•Version 4.8: Adjusted to make the domain less punishing, with fewer enemies and a less severe Ley Line Disorder effect.
•Enemy Adjustments: Periodic tweaks to enemy health, attack patterns, and AI to match player power creep.
•Artifact Sets: No major changes to the core sets, but subtle adjustments to drop rates or set effects might occur for balance.
This guide should help you navigate and master The Lost Valley Domain, optimizing your artifact farming in "Genshin Impact".
