The part of Shiyu Defense you farm forever is five stages long. Each one takes two teams of three Agents who cannot share a member, each team brings its own Bangboo, and clearing all five at S-Grade pays 780 Polychrome per cycle. The rotation turns over every 14 days on a Friday at 04:00 server time, and the Frontier Effect live right now resets on October 2, 2026.
That is the whole shape of the mode. Everything below is how each piece works, what it pays, and what to do differently when the cycle flips.
Three node types, and only one of them repeats
Shiyu Defense unlocks at Inter-Knot Level 35, once you have been promoted to Certified Proxy and cleared the commission that introduces it. Inside, it splits into three sections that behave nothing alike:
| Node | Repeats? | Shape | What it pays |
|---|---|---|---|
| Stable | No | Stages unlock one at a time as you clear | 100 Polychrome per challenge target; 3,000 for all targets across ten Defenses |
| Disputed | No | No time limit, graded on whether your team survives | One-time Polychrome, materials, Dennies |
| Critical | Yes, every 14 days | Five stages, two teams each, scored on speed | Up to 780 Polychrome per cycle |
The Stable and Disputed Nodes are a one-time bank of several thousand Polychrome sitting behind your roster's current ceiling. They never refresh, so there is no rush and no penalty for leaving a stage you cannot beat yet. Come back after two more Agent ascensions and take it then.
The Critical Node is the one that matters on a schedule. It currently runs five Frontiers, down from seven since Version 2.5, and it is the mode people mean when they say "Shiyu Defense" without qualifying it.
Frontier Effects buff Attributes, not factions
This is the mechanic most guides describe loosely, including an earlier version of this one, so here it is precisely.
Every Critical Node cycle applies a Frontier Effect, and it is the same effect across all five stages. It comes in two halves:
- Attribute Buffs. Up to two Attributes get buffed for the cycle, and deploying Agents of those Attributes gives you a combat bonus. Attribute means Fire, Ice, Electric, Ether or Physical. It does not mean faction, so Cunning Hares or Sons of Calydon membership buys you nothing here.
- Special Buffs. A bonus attached to a fighting style or a squad shape rather than an element, for example extra Aftershock and EX Special damage, or reduced recovery speed on Stunned enemies. Game8's current writeup of the 3.2 rotation gives Room 1 a 25% Sharp DMG increase, 15% DEF, and a 20% Stun DMG Multiplier bonus on critical hits against Stunned enemies for 10 seconds.
Both halves are activated by how you arrange the squad, and the effect sheet is on the pre-battle screen next to the enemy weakness and resistance list. Read it before you lock anything in, because the buffed Attributes move each cycle and an off-Attribute carry can lose more damage than a two-constellation gap would give you.
If you want the pairings that tend to line up with whatever the cycle buffs, the Shiyu Defense team tier list ranks them as pairs rather than as single Agents, which is the correct unit of analysis for a two-team mode.
The reuse rule, and why Deadly Assault is the opposite
Inside a single Critical Node stage you field two teams, and no Agent or Bangboo can appear in both. That is the constraint that makes the mode a roster test rather than a damage test.
What trips people up is the scope. The lock is per stage, not per cycle: the same six Agents can clear stage 1 and then walk into stage 2. Deadly Assault, the sister mode, works the other way, and mixing them up costs you a cycle of rewards.
| Shiyu Defense (Critical Node) | Deadly Assault | |
|---|---|---|
| Unlocks at | Inter-Knot 35 | Inter-Knot 40 |
| Teams needed | 2 per stage, reusable across stages | 3, locked for the whole rotation |
| Scored on | Clear speed against a target time | Points: damage, Daze, mechanic bonuses |
| Max Polychrome | 780 per cycle | 300 per cycle |
| Resets | Every 14 days, Friday 04:00 | Every 14 days, Friday 04:00 |
So Shiyu Defense rewards one deep pair you can re-field five times. Deadly Assault punishes exactly that, because an Agent spent on boss one is gone for bosses two and three. The Deadly Assault team tier list covers that split, and the Deadly Assault guide has its scoring.
What a full clear pays, grade by grade
Each Critical Node stage carries three reward tiers, awarded on how far under the target time you finish:
- B-Grade: you cleared it.
- A-Grade: you beat the target time.
- S-Grade: you beat it comfortably.
Two things follow from that, and both are good news for a thin account. Clearing a stage at any grade unlocks the next one, so a scrappy B on stage 3 still opens stage 4 and its rewards. And because the 780 Polychrome is the sum of fifteen separate grade rewards rather than one payout at the end, a partial run is worth doing. There is no all-or-nothing gate.
Practically: take the B on the stage your roster hates, then spend your real effort on the stages where your buffed-Attribute carry can hit S. Points, like Polychrome, are a total.
When the cycle turns, and how the two modes interleave
The two endgame modes reset on the same 14-day cadence but a week apart, which is what gives ZZZ a weekly endgame rhythm rather than a fortnightly one:
| Mode | Current cycle ends | Next boundary (projected) |
|---|---|---|
| Shiyu Defense, Critical Node | Friday, October 2, 2026 | Friday, October 16, 2026 |
| Deadly Assault | Friday, October 9, 2026 | Friday, October 23, 2026 |
The October 2 and October 9 dates are the published ones. The right-hand column is the 14-day cadence carried forward, not a date HoYoverse has posted, so treat it as a planning estimate that a version launch can shift.
Dates are the reset boundary at 04:00 server time. The practical habit: clear the Critical Node in the first weekend of its cycle while the Attribute buffs are fresh in your head, and leave the second weekend for Deadly Assault's three-team puzzle. If you are saving the Polychrome either mode pays, check the ZZZ banner schedule before you spend it.
Gearing that survives a rotation change
Because the buffed Attributes move every cycle, the builds that hold up are the ones that do not depend on the cycle agreeing with them:
- Get the main stats right before touching substats. A Sands with flat ATK instead of ATK% cannot be repaired, only replaced. The drive disc substats guide has the priority order per role.
- Aim for roughly 60% CRIT Rate and 120% CRIT DMG on a primary carry before you chase anything else. Anomaly carries swap that for Anomaly Proficiency and ATK%, since their damage does not crit in the same way. The anomaly teams guide explains that split.
- Finish four-piece sets on your two best carries rather than spreading two-piece bonuses across four Agents. Chaotic Metal and Fanged Metal sit on Anomaly builds, Shockstar Disco on Electric Stun, Polar Metal on Ice; per-Agent recommendations live on the ZZZ tier list.
- Bring a Bangboo on both teams. An empty slot is free performance discarded, and a faction-matched Bangboo's bonus is stronger than a generic one's, which is the one place faction still does something in this mode.
A second team built to roughly 70% of your first will clear most of the Critical Node. What it will not do is carry a stage whose buffed Attribute it cannot touch, which is the argument for breadth over one perfected squad.
Before you queue into stage 5
Check these and the back half of the Critical Node stops being a wall:
- Two teams of three, no Agent or Bangboo shared inside the stage.
- Each team has a carry, something that Stuns or applies Anomaly, and a source of sustain or shielding.
- Your two carries are on four-piece sets with correct main stats.
- At least one team matches an Attribute the current Frontier Effect buffs.
- You have read the enemy resistance list on the pre-battle screen, not just the recommended level.
Short of Polychrome to fill the gap that keeps showing up? The ZZZ codes page is the free source, and it is refreshed as codes land and die rather than left to rot.
Sources for the mechanics and dates above: Game8's Shiyu Defense guide and reset and its 3.2 Critical Node writeup, GameVika's Shiyu Defense wiki entry, Theria Games' Frontier Effect breakdown, and HoYoLAB's community documentation of the Stable Node reward targets. Verified 2026-09-29.
