Alhaitham

• Can deal high single and multi-target DMG.
• Flexible to perform all Dendro-related reactions on-field.
• Extremely fast Dendro application.
• Infusion cannot be overriden, and it's not tied to Burst.

Alhaitham's best weapon is his sig Light of Foliar Incision

Some other Good weapons for him are

• Uraku Misugiri
• Primordial Jade Cutter
• Wolf-Fang
• Iron Sting

His best artifact set is Gilded Dreams

Artifact Main Stats

• Sands: Elemental Mastery
• Goblet: Dendro DMG Bonus
• Circlet: CRIT Rate or CRIT DMG

Artifact Sub-Stats

Elemental Mastery, Energy Recharge, CRIT Rate, CRIT DMG, ATK%

It is Recommended that you give him 130% or more Energy Recharge

Some good teams are

Quickbloom

• Alhaitham
• Nahida
• Kuki Shinobi
• Yelan

Spread

• Alhaitham
• Nahida
• Yae Miko
• Zhongli

Talent Priority

1. Elemental Skill
2. Normal Attack
3. Elemental Burst

Alhaitham Ascension Materials

• Mora ×420,000
• Nagadus Emerald Sliver ×1
• Nagadus Emerald Fragment ×9
• Nagadus Emerald Chunk ×9
• Nagadus Emerald Gemstone ×6
• Faded Red Satin ×18
• Trimmed Red Silk ×30
• Rich Red Brocade ×36
• Sand Grease Pupa ×168
• Pseudo-Stamens ×46

Alhaitham Talent Materials

• Mora ×4,957,500
• Crown of Insight ×3
• Teachings of Ingenuity ×9
• Guide to Ingenuity ×63
• Philosophies of Ingenuity ×114
• Faded Red Satin ×18
• Trimmed Red Silk ×66
• Rich Red Brocade ×93
• Mirror of Mushin ×18

I own this character