Genshin Impact Trial of the Bastion Day 3: Crossfire Attack Guide

Stage III of Trial of the Bastion, called Crossfire Attack, is the third daily trial in Genshin Impact’s Version 7.0 base defense event. It drops you into an icy arena with a single enemy spawn portal, a set of buildable mechanisms, and a firearm loadout, and asks you to keep three waves of Snezhnayan attackers away from your stronghold. The scoring is generous once you understand how the traps feed off each other.

Quick answer: Pair a Suppression Device: Blaze with an Ice Mist Trap on the enemy path so every runner takes Melt damage, shoot Surprise Strikers the moment they appear to upgrade all your mechanisms, and you will clear the 4,500 challenge rating with room to spare. A full clear can push past 6,600 points.

Crossfire Attack score targets and rewards

Crossfire Attack has three scoring objectives rather than a pass/fail clear. Every enemy you kill adds to a single challenge rating, and each threshold you cross unlocks another reward tier that you collect from the event menu afterwards.

Detail	Value
Stage	Stage III — Crossfire Attack
Unlock date	September 9, 2026
Waves	3
Stronghold HP	20
Score objectives	2,000 / 3,000 / 4,500 challenge rating
Primogems	80 total (50 + 30)
Other rewards	60,000 Mora, 6 Mystic Enhancement Ore, 4 The Frost-Bound Emperor’s Pride

The whole event runs from September 7 to September 17, 2026, and a new trial unlocks each day for the first five days. Each one only appears after you finish the previous stage, so if Crossfire Attack is greyed out, go back and complete Triple Assault first.

How to open Stage III

You need Adventure Rank 20 or higher, the Archon Quest Prologue Act III “Song of the Dragon and Freedom”, and the “Gunfire in the Silent Lands” quest from Chapter VII Act I “Everwinter Without Mercy”. The event proper also gates itself behind a short introductory quest, “A Grueling Combat Simulation”, which you can start from the World Quests tab or the event page.

Open the Events Overview menu, pick Trial of the Bastion, and hit Go to Challenge. That teleports you straight to the simulation site rather than making you walk there.

Talk to Talalikhin, the NPC standing beside the simulation console, and run through the dialogue to boot up the trial.

Choose Stage III, Crossfire Attack. The selection screen shows the opposing lineup, your firearm loadout, and the mechanisms available to build. Confirm with Start Challenge.

Crossfire Attack stage select screen with the Start Challenge button ready to confirm — The Crossfire Attack briefing screen, where Start Challenge launches the trial. Image: HoYoverse

Mechanisms and what each one does

Mechanisms are paid for with construction materials, and you get 500 more every time you clear a wave. That means your defense is meant to grow between waves instead of being fully built at the start. Some mechanisms can also be rotated to face a more useful direction during the preparation phase.

Mechanism	What it does
Suppression Device: Blaze	Applies Pyro to enemies moving through its area
Ice Mist Trap	Applies Cryo, and sets up Melt when combined with Blaze
Spike Mechanism	Direct damage laid along the enemy path
Impact Shield	Barrier that stalls enemies at a chokepoint
Pulling Mechanism	Drags enemies together so groups take trap damage at once

The Blaze and Ice Mist combination is the core of a high score here. Enemies pick up one element from the first mechanism and the second reaction triggers Melt, which does most of the heavy lifting while you focus on aiming.

Wave-by-wave plan for Crossfire Attack

During the opening preparation phase, walk the arena and grab the ammo boxes before you build anything. The assault rifle empties fast, and running dry mid-wave is the most common reason a run stalls out.

Place the Suppression Device: Blaze and the Ice Mist Trap close together on the lane the enemies use, then start the first wave. Hold your position behind the traps and fire into the crowd as it funnels through. The assault rifle’s charged shot punches through several bodies in a line, so wait for enemies to stack up before you use it.

Wave 1 of 3 underway with the defend your stronghold banner across the screen — The banner confirming Wave 1 of 3 has started and enemies are inbound. Image: HoYoverse

After the wave clears, sweep the arena for dropped construction materials and ammo. Spend the new materials on an Impact Shield to hold enemies in the trap zone and a Pulling Mechanism to bunch them up. When the layout looks right, use the Engage Now prompt to call in the second wave early instead of waiting out the timer.

Engage Now prompt on screen during the preparation phase between waves — The Engage Now prompt appears once the preparation phase is running, letting you start the next wave on your terms. Image: HoYoverse

Wave 2 brings elites alongside the regular runners. Keep firing into the trap zone and let the newly built mechanisms grind down the tougher targets while you finish off whatever slips past.

A blue holographic mechanism materializing on the field as enemies close in — A mechanism deploying mid-defense as the wave pushes toward the stronghold. Image: HoYoverse

Before the last wave, move your placements closer to the spawn portal and add Spike Mechanisms and another Impact Shield. Killing enemies right at the portal buys you time and keeps the fight far from the stronghold.

Highlighted Engage Now button being selected to trigger the final wave — Selecting Engage Now to send in the final wave once the mechanisms are repositioned. Image: HoYoverse

The third wave sends roughly 20 enemies, including the remaining elites. Keep the trigger held on the assault rifle, top up from ammo crates between groups, and let the Melt reactions from your traps finish the tanky targets.

Tip: Frag grenades work well against clustered elites, but they can lodge in walls if you throw them from too far away. Stay at a moderate distance so the arc lands where you want it.

Surprise Strikers are the biggest score swing

Surprise Strikers show up during the challenge carrying special rewards. Killing one enhances every active mechanism on the field at once and hands you tactical gear. Because the buff applies to all of your traps simultaneously, taking these targets down early in a wave multiplies the damage everything else deals for the rest of the run. If a Striker appears while you are dealing with regular enemies, switch to it first.

Confirming the clear and claiming the rewards

When the final enemy of Wave 3 dies, the Challenge Complete screen appears with your total score. Anything above 4,500 satisfies all three objectives at once, and a clean run with Melt traps and Striker buffs can land in the 6,600 range, so there is a comfortable margin.

The rewards do not land in your inventory automatically. Exit the challenge, open the Trial of the Bastion rewards menu, and claim each tier you passed. The Primogems, Mora, Mystic Enhancement Ore, and The Frost-Bound Emperor’s Pride all sit there until you collect them.

Two things end a run early. The stronghold’s HP bar starts at 20 and drops as enemies get past your defenses, and running out of ammo at the wrong moment lets a wave walk straight through. Sweeping for ammo crates during every preparation phase solves both, since a loaded rifle is what keeps enemies pinned inside the trap zone in the first place.

Once Crossfire Attack is done, Stage IV unlocks on the following day’s reset, so there is no reason to leave the third trial sitting unfinished if you want the full event reward track before it closes on September 17.