King in Check in HSR Anomaly Arbitration: How to Break the Shield with Elation Teams

King in Check is the final boss of the Anomaly Arbitration mode in Honkai: Star Rail. The fight is built around a shield phase, and the fastest way through it is a team that stacks rapid follow-up attacks to strip the shield and end the second phase before the cycle limit runs out.

Quick answer: Bring an Elation follow-up core built around Aventurine · Waveflair with Yao Guang and Pearl for constant attack frequency, or an Ashveil plus Mortenax Blade DEF-shred shell. Break the shield in the phase-two transition, then burst the boss before you hit the cycle cap. You have cleared it when the Battle Over screen appears with your stars awarded.

Why the shield phase decides the fight

The King in Check encounter gates its second phase behind a shield. Until that shield is broken, damage into the boss is heavily reduced, so a team that cannot generate enough hits will stall out. This is why raw single-hit damage matters less here than how many times your party attacks per turn.

Elation follow-up teams solve this directly. Every teammate action feeds the follow-up loop, and each of those extra hits chips the shield. Once the shield falls, the boss enters its final phase and takes full damage, which is where your burst window matters most.

Team 1: Elation follow-up core

The first reliable comp pairs Aventurine · Waveflair as the Quantum Elation carry with Yao Guang and Pearl to keep attack frequency high. Waveflair gains Fervor and Punchlines every time a teammate attacks, so the more actions your supports take, the faster he auto-fires his Elation Skill and bounces damage across the boss.

Pearl slots in as the Elation sustain, which lets you run a full Elation lineup without giving up healing. Yao Guang drives the follow-up rotations that break the shield during the phase-two transition. With this setup, the shield comes down through sheer volume of hits rather than one big nuke.

Team 2: Ashveil and Mortenax Blade DEF-shred shell

The second approach swaps the resource-generation core for a DEF-shred shell. Aventurine · Waveflair still carries, but here he is backed by Mortenax Blade, Ashveil, and Hyacine. Ashveil brings teamwide DEF Shred, which raises the damage everyone deals into the shield and the boss underneath it.

Mortenax Blade adds a second heavy damage source, while Hyacine covers sustain so the party survives the boss’s phase-two pressure. This shell trades some of the follow-up volume of the first team for bigger individual hits, and it clears the same shield gate through DEF reduction instead.

How to break the shield and finish the run

You know it worked when the Battle Over screen appears and your star rating is awarded. If the run stalls, it is almost always because the shield never broke in time, which points to too few attacks per turn or missing DEF reduction rather than a lack of raw damage.

Aventurine · Waveflair build for both teams

Waveflair anchors both comps, so his stat line matters most. He wants 160 or more SPD as a baseline, since a major Trace converts excess speed into Elation damage. Stack high CRIT alongside that speed to make each follow-up hit count.

His signature Summer Rides the Surf provides a CRIT Rate boost and speed and Elation damage buffs on Elation Skill use, which is why it sits at the top of both team sheets. The 160 SPD threshold is the single most important breakpoint, since it switches on his damage-per-speed scaling for the whole fight.

Both teams clear the same shield gate, just through different means. If you own a full Elation lineup with Pearl as sustain, the follow-up core keeps its damage steady across the whole encounter. If your roster leans on Ashveil and Mortenax Blade instead, the DEF-shred shell gets you to the same Battle Over screen by making every hit land harder.