Si joins Arknights: Endfield Version 1.6, Sanctuary of Ink, as a 6-star Cryo Supporter. She specializes in elemental damage amplification, Combo Skill interactions, and a unique Inksoul mechanic that lets teammates attack a stationary target instead of chasing moving enemies. Although she uses a Greatsword, her biggest strength comes from supporting Cryo and Heat teams while contributing additional damage.

This Si build guide covers her abilities, best weapons, gear, Essence choices, team compositions, gameplay rotation, and pull advice.

If you usually play Arknights: Endfield on PC but want to continue exploring while away from your desk, OSLink offers a convenient way to remotely access your PC from your phone. You can check your game progress, manage factory production, collect materials, and continue playing the PC version on your mobile device without switching to a separate mobile game session. It's especially useful when you're busy but still want to make progress toward Si's upgrades.

Si Overview and Role

Si is a flexible Supporter who improves elemental damage while helping teammates maintain pressure against mobile enemies.

Her effectiveness depends heavily on elemental Inflictions and team order. Rather than building her as a conventional main DPS, the best builds for Si focus on supporting a strong elemental carry while also boosting her own Combo Skill damage.

Si Skills and Combat Mechanics

Si's abilities revolve around two important mechanics: Artful Intent and Inksoul.

Artful Intent records a portion of the damage dealt to a marked enemy and releases it as area Fixed DMG when the effect expires.

Inksoul creates a stationary target linked to an enemy. Damage and effects applied to the Inksoul are transferred to its host, making it particularly useful against enemies that frequently move or teleport.

Brushwork Realm can also transition into additional actions that summon an Inksoul and detonate it early.

The most important detail is team position. Si's elemental application and Ultimate cooldown support depend on who occupies the first slot.

Si Best Builds: Weapons, Gear, and Essence

Best Si Weapon

Best Si Gear

Type 50 Yinglung is promising because its set bonus enhances Combo Skill damage after teammates use Battle Skills.

Eternal Xiranite can work in support-oriented setups, but its team buff does not stack with another copy of the same effect.

Best Si Essence Stats

Weapon Essence optimization should prioritize attributes that match the equipped weapon's skills.

For Jade Vessel, look for an Essence matching Intellect, Cryo DMG, and Efficacy.

Avoid spending heavily on unrelated Essence bonuses simply because they provide higher raw numbers.

Play Arknights Endfield PC on Your Phone via OSLink!

Pre-set Keymaps for Easy Play

Controller Supported on Mobile

Low Latency, Smooth Control

Cross-Platform Support

https://apps.apple.com/app/id6444689630 https://hwres.ldmnq.com/remote/apk/OSLink.apk Download OSLink & Remote Play [Arknights Endfield]

Best Si Team Compositions

The best Si team should consistently apply and consume Cryo or Heat Inflictions.

For a Si-centered Cryo team, place Si in the first position to benefit from her own Ultimate's Combo Skill cooldown reduction.

For Laevatain teams, place Laevatain first. This allows Si to apply Heat Infliction and strengthen the team's Heat-focused rotation.

Xaihi and Ardelia provide valuable healing, helping these teams maintain their offensive rhythm.

Si Gameplay and Rotation

Playing Si effectively depends more on timing elemental reactions than on repeatedly switching to her for Basic Attacks.

A practical rotation is:

Apply Infliction → Use Brushwork Realm → Create Inksoul → Trigger Allied Elemental Reactions → Activate Combo Skill → Use Ultimate.

Start by preparing the appropriate elemental Inflictions, then apply Artful Intent to the main target.

Use the Inksoul to maintain damage when enemies move away. Coordinate your teammates' Infliction-consuming abilities to activate Fully Envisioned.

Save her Ultimate for meaningful damage windows so your main carry benefits from Cryo or Heat amplification.

Remember that Si's Combo Skill requires the correct elemental interaction. Simply applying Inflictions without consuming or absorbing them will not automatically trigger it.

Should You Pull Si? Si Pull Advice

Si appears on the Rejuvenation Chartered Headhunting banner from October 15 to November 5, 2026.

She is especially attractive if you already use Laevatain, Yvonne, or another Cryo/Heat damage dealer.

Her ability to provide elemental amplification, Combo Skill support, and Inksoul utility makes her a valuable addition to compatible teams.

However, she is less compelling for accounts primarily focused on Physical, Electric, or Nature damage, since her elemental amplification does not directly benefit those carries.

Our recommendation: Pull Si if you want to strengthen an existing Cryo or Heat team, but prioritize obtaining one copy before investing heavily in her signature weapon or additional Potentials.

Overall, Si offers a distinctive support playstyle with excellent potential in elemental compositions. Focus on compatible weapons, Combo Skill-oriented gear, and teammates who can reliably trigger her abilities. And if you want to continue managing your Endfield progress while away from your computer, OSLink makes it convenient to access the PC version from your phone and keep working toward your next upgrades.