Arlecchino is a damage dealer who uses the Bond of Life to gain offensive buffs.
She can use her Elemental Skill to apply Blood-Debt Directives and obtain the Bond of Lide. When the Bond of Life reaches a certain percentage of her Max HP, Arlecchino's Normal Attacks will be converted to deal Pyro DMG as well as deal increased DMG.
Her Elemental Burst deals AoE Pyro DMG, removing the remaining CD of her Elemental Skill and restoring her HP.

This guide is based on the Community Character Builds by the Genshin Helper Team.

Skills Overview

Normal Attack: Invitation to a Beheading

Normal Attack
Performs up to 6 consecutive spear strikes.

Plunging Attack
Plunges from mid-air to strike the ground below, damaging opponents along the path and dealing AoE DMG upon impact.

Charged Attack
Consumes a fixed amount of Stamina, dashing toward a nearby opponent and cleaving once.
Continuously holding this button will cause Arlecchino to consume Stamina and engage in up to 5s of high-speed movement.

Masque of the Red Death
When Arlecchino has a Bond of Life equal to or greater than 30% of her Max HP, she will enter the "Masque of the Red Death" state, where her Normal, Charged, and Plunging Attacks will be converted to deal Pyro DMG. This cannot be overridden.
When in the "Masque of the Red Death" state, Arlecchino's Normal Attacks will deal extra DMG to opponents on hit that scales off her ATK multiplied by a certain ratio of her current Bond of Life percentage. This will consume 7.5% of said current Bond of Life. Her Bond of Life can be consumed this way every 0.03s. When her Bond of Life is consumed in this manner, All Is Ash's CD will decrease by 0.8s.

Elemental Skill: All Is Ash

Summons forth Balemoon Bloodfire, dealing Pyro DMG to multiple nearby opponents and performing a dash-cleave against one of them, dealing AoE Pyro DMG.
Opponents hit by the aforementioned attack will have a Blood-Debt Directive applied to them.

Cooldown: 30 seconds

Blood-Debt Directive
• Lasts 30s. Every 5s, it will deal 1 instance of Pyro DMG to the opponent. Max 2 instances. This DMG will be considered Elemental Skill DMG.
• When Arlecchino uses a Charged Attack or her Elemental Burst, Balemoon Rising, she will absorb and clear nearby Blood-Debt Directives. Each Directive absorbed grants her a Bond of Life worth 65% of her Max HP.
• The maximum value of the Bond of Life she can be granted through Blood-Debt Directives within 35s after using her Elemental Skill is 145% of her Max HP. Using the Elemental Skill again during this duration will restart the count on duration and the limit on the value of Bond of Life she may gain from Blood-Debt Directives.

Elemental Burst: Balemoon Rising

Arlecchino's great wing of Balemoon Bloodfire beats as she absorbs and clears Blood-Debt Directives around her. She deals AoE Pyro DMG before clearing the CD of All Is Ash and healing herself. The healing is based on her Bond of Life value and ATK.

Cooldown: 15 seconds
Energy Cost: 60

Ascension 1: Agony Alone May Be Repaid

Blood-Debt Directives have the following characteristics:
• Arlecchino will be granted a Bond of Life worth 130% of her Max HP when an opponent to which she herself applied a Directive is defeated.
• 5s after a Directive is applied, it will be upgraded to a Blood-Debt Due. When absorbed, it will instead grant Arlecchino a Bond of Life worth 130%.
A Bond of Life created in the aforementioned ways cannot exceed the original limit on the value of Bonds of Life obtained through All Is Ash.

Ascension 4: Strength Alone Can Defend

Arlecchino gains 1% All Elemental and Physical RES for every 100 ATK she has in excess of 1,000. The maximum RES increase she can gain this way for each is 20%.

Passive Talent: The Balemoon Alone May Know

While in combat, Arlecchino gains a 40% Pyro DMG Bonus and can only be healed through Balemoon Rising.

TLDR / Rotation

In short, what you need to do is use Arlecchino's Elemental Skill to enemies (to inflict Blood-Debt Directive) and switch to other characters to use their Skills/Bursts. After 5 seconds or more has passed, the previous Blood-Debt Directive will upgraded to Blood-Debt Due.

Once you're sure the enemies has Blood-Debt Due, use Arlecchino's Charged Attack to absorb the Blood-Debt Due to grant her Bond of Life. As long as Arlecchino has Bond of Life equal to or greater than 30% of her Max HP, all her damage will be converted to Pyro DMG.

General Rotation: Arlecchino's Skill > Switch to other characters and use their Skill/Burst > Arlecchino's Charged ATK to gain Bond of Life > Spam Normal Attack > Repeat.

C2 Rotation (Different because her Skill will immediately grant Blood-Debt Due to enemies instead of Blood-Debt Directive): Support characters > Arlecchino's Skill > Charged Attack > Spam Normal Attack > Ultimate (Optional) > Repeat.

Talent Priorities

Normal Attack > Skill > Burst

*Her Burst’s healing is not dependent on Talent levels

Constellations

Best Constellations: C1, C2 & C6

C1: "All Reprisals and Arrears, Mine to Bear…" ⭐
Masque of the Red Death is further enhanced, the value of the increase is 100%. Additionally, Arlecchino's interruption resistance is increased when she performs Normal or Charged Attacks while affected by the Masque of the Red Death.

C2: "All Rewards and Retribution, Mine to Bestow…" ⭐
Blood-Debt Directives are now already Blood-Debt Due when first applied.
When Arlecchino absorbs such a Due, she unleashes Balemoon Bloodfire in front of her, dealing 900% of her ATK as AoE Pyro DMG and increasing her All Elemental RES and Physical RES by 20% for 15s. This effect can trigger once every 10s.
You must first unlock the Passive Talent "Agony Alone May Be Repaid."

C3: "You Shall Become a New Member of Our Family…"
Increases the Level of Normal Attack: Invitation to a Beheading by 3.
Maximum upgrade level is 15.

C4: "You Shall Love and Protect Each Other Henceforth…"
When Arlecchino successfully absorbs a Blood-Debt Directive, Balemoon Rising's CD will decrease by 2s and 15 Elemental Energy will be restored to her. This effect can occur once every 10s.

C5: "For Alone, We Are as Good as Dead…"
Increases the Level of Balemoon Rising by 3.
Maximum upgrade level is 15.

C6: "From This Day On, We Shall Delight in New Life Together." ⭐
The DMG of Balemoon Rising is increased by Arlecchino's ATK multiplied by 700% of Arlecchino's current Bond of Life percentage.
For 20s after Arlecchino uses All Is Ash, both her Normal Attacks and Elemental Burst gain 10% increased CRIT Rate and 70% increased CRIT DMG. This effect can be triggered up to once every 15s.

Recommended Weapons

1. Crimson Moon’s Semblance (5⭐)
2. Primordial Jade Winged-Spear (5⭐)
3. Staff of the Scarlet Sands (5⭐)
4. Staff of Homa (5⭐)
5. Deathmatch (4⭐)
6. Ballad of the Fjords (4⭐)
7. White Tassel (R5) (3⭐)

1) Crimson Moon’s Semblance (ATK: 674 • Crit Rate: 22.1%)

Grants a Bond of Life equal to 25% of Max HP when a Charged Attack hits an opponent. This effect can be triggered up to once every 14s. In addition, when the equipping character has a Bond of Life. they gain a 12/16/20/24/28% DMG Bonus; if the value of the Bond of Life is greater than or equal to 30/32/40/48/56% of Max HP, then gain an additional 24% DMG

2) Primordial Jade Winged-Spear (ATK: 674 • Crit Rate: 22.1%)

Increases CRIT Rate by 8/10/12/14/16% and increases Normal ATK SPD by 12%. Additionally, Normal and Charged Attacks hits on opponents have a 50% chance to trigger a vaccuum blade that deals 40/55/70/85/100% of ATK as DMG in a small AoE. This effect can occur no more than once every 2s.

3) Staff of the Scarlet Sands (ATK: 542 • Crit Rate: 44.1)

The equipping character gains 52/65/78/91/104% of their Elemental Mastery as bonus ATK. When an Elemental Skill hits opponents, the Dream of the Scarlet Sands effect will be gained for 10s: The equipping character will gain 28/35/42/49/56% of their Elemental Mastery as bonus ATK. Max 3 stacks.

4) Staff of Homa (ATK: 608 • Crit DMG: 66.2%)

HP increased by 20/25/30/35/40%. Additionally, provides an ATK bonus based on 0.8/1/1.2/1.4/1.6% of the wielder's max HP. When the wielder's HP is less than 50%, this ATK bonus is increased by an additional 1/1.2/1.4/1.6/1.8% of max HP.

5) Deathmatch (ATK: 454 • Crit Rate: 36.8%)

If there are at least 2 opponents nearby, ATK is increased by 16/20/24/28/32% and DEF is increased by 16/20/24/28/32%. If there are less than 2 opponents nearby, ATK is increased by 24/30/36/42/48%.

6) Ballad of the Fjords (ATK: 510 • Crit Rate: 27.6%)

When there are at least 3 different Elemental Types in your party, Elemental Mastery will be increased by 120/150/180/210/240.

7) White Tassel (ATK: 401 • Crit Rate: 23.4%)

Increased Normal Attack DMG by 24/30/36/42/48%.

Recommended Artifacts

1. Fragment of Harmonic Whimsy (4)
2. Gladiator’s Finale (4)
3. Crimson Witch of Flames (4)
4. Gilded Dreams (4)
5. Crimson Witch of Flames (2) / Gladiator’s Finale (2)

1) Fragment of Harmonic Whimsy

2-Piece Bonus: ATK +18%
4-Piece Bonus: When the value of a Bond of Life increases or decreases, this character deals 18% increased DMG for 6s. Max 3 stacks.

2) Gladiator’s Finale

2-Piece Bonus: ATK +18%
4-Piece Bonus: If the wielder of this artifact set uses a Sword, Claymore, or Polearm, increases their Normal attack DMG by 35%.

3) Crimson Witch of Flames

2-Piece Bonus: Pyro DMG Bonus +15%
4-Piece Bonus: Increases Overloaded and Burning, and Burgeon DMG by 40%. Increases Vaporize and Melt DMG by 15%. Using Elemental Skill increases the 2-Piece Set Bonus by 50% of its starting value for 10s. Max 3 stacks.

4) Gilded Dreams

2-Piece Bonus: Elemental Mastery +80
4-Piece Bonus: Within 8s of triggering an Elemental Reaction, the character equipping this will obtain buffs based on the Elemental Type of the other party members, ATK is increased by 14% for each party member whose Elemental Type is the same as the equipping character, and Elemental Mastery is increased by 50 for every party member with a different Elemental Type. Each of the aforementioned buffs will count up to 3 characters. This effect can be triggered once every 8s. The character who equips this can still trigger its effects when not on the field.

5) Crimson Witch of Flames + Gladiator’s Finale

ER Requirement:
Solo Pyro: 150%+
Double Pyro: 140–150%
Triple Pyro: 120%

Team Compositions

Vaporize Team

Arlecchino: Main DPS
Xingqiu: Hydro off-field application
Yelan: Hydro off-field application | Bennett: Buffer
Zhongli: Shielder + Elemental RES Shred | Kazuha: CC + VV set

Mono Pyro Team

Arlecchino: Main DPS
Bennett: Buffer
Zhongli: Shielder + Elemental RES Shred | Kazuha: CC + VV set
Chiori: Sub-DPS | Xiangling: Off-field Sub-DPS

Overload Team

Arlecchino: Main DPS
Chevreuse: Pyro & Electro RES Shred
Fischl: Off-field Sub-DPS
Bennett: Buffer