Arknights Vector Breakthrough #3 "Pseudo-Ecology" Guide: 12-Floor Core Breakthrough Squads and Special Front Tactics

The rule that defines this entire event: every stage sets your protection objective to 1 HP. One leaked enemy and you restart. So the correct squad-building goal is "never leak" first and "deal damage" second. Shift, block and crowd-control operators carry far more value here than they do in a normal stage.

Arknights Vector Breakthrough #3 Dates and Rewards

When it runs and how to unlock it

The only unlock requirement is clearing Main Story 2-10. A new account can enter as soon as chapter two is done. The "Resource Collection" stages also run open all day for the whole event window (Sep 29 16:00 - Oct 20 03:59), which makes that period far better than usual for LMD and battle records.

What the Breakthrough Milestone actually gives

The Breakthrough Milestone stays open three days longer than the stages, closing October 23 at 03:59. Headline rewards include the outfit "Times Series - Lazy Humming - Scene" , event furniture, module development materials, high-tier development materials, battle records and LMD.

Inside that pool, module materials are the scarce item. LMD and battle records have permanent farms plus the open-all-day Resource Collection stages as a backstop; module materials only see concentrated drops during events like this one. Recommended redemption order: module data and high-tier development materials first, battle records second, LMD and furniture third, outfits last.

Arknights Core Breakthrough Mechanics: 12 Floors and Misery

Floor progression and the difficulty curve

Floors 1-5 unlock when the event opens; floors 6 and up require clearing the previous floor first. The 1-HP protection objective applies across the board, which invalidates the old habit of brute-forcing with high-HP stalling squads.

Two details matter for pulling off high floors. First, instructor Misery appears on floors 4, 8 and 12, where both the instructor and the adds scale up and the instructor gains extra abilities . Second, repeat clears of floors you have already finished still pay a small amount of the event currency, "Slippery Floor".

That second point is the most underrated efficiency play of the event. Low floors have stable clear times and low failure rates, so farming floors 1-9 on repeat can out-produce stubborn attempts on floors 11 and 12 in terms of currency per hour.

Arknights Special Front: Seize Control and Battle Supplies

The 180-second rule and garrison requirements

Special Front unlocks after you clear floor one and its stages unlock in four batches. Tapping "Seize Control" lets you bring a small squad - no support operators allowed - and you must defeat the enemies inside the node within 180 seconds and then leave an operator to garrison it.

Two restrictions shape everything. No support operators means your own roster depth decides the node difficulty. Garrisoning means an operator parked in a node cannot appear in your Core Breakthrough squad, a hidden manpower tax. Send your permanent benchwarmers to garrison and keep main carries and key controllers at home.

How Battle Supplies are meant to be used

Battle Supplies grant extra buffs inside Core Breakthrough and the higher-difficulty Full Power mode. They exist to lower Core Breakthrough's difficulty, so the correct order is: clear Special Front first, spread the supplies, then come back for Core Breakthrough's upper floors. Doing it in reverse means ramming a stage that was designed to be attempted with buffs using a bare squad.

Arknights Vector Breakthrough #3 Squad Recommendations

Three squad setups

Squad	Operators	Equipment / modules	Skill order
Hold-fast (low investment)	2 vanguards, 1 defender, 2 medics, 3 DPS	Defender module first	Vanguards generate DP, defender plugs the main lane, medics follow, DPS clears side lanes
Shift control (mid-game)	2 shifters, 1 slow supporter, 2 snipers, 2 medics	Shift-operator module	Push enemies into pits, slow the second wave, snipe high-HP targets
High-end speed	Caster carry, elemental healer, AoE control, 2 finishers	Damage modules on carries	Control locks the field, caster bursts, finishers clean up, medic stabilizes

Placement principles

Do not commit every deployment slot at the start. With a 1-HP objective, a single uncovered lane ends the run. Holding 1-2 slots in reserve for a surprise wave is safer than a full opening board. All three squads can clear floors 1-9; for floors 10 and up, fill out your Battle Supplies first.

Arknights Vector Breakthrough #3 Operator Investment Priority

Who to mastery-train

Prioritize by usage frequency, not rarity. A six-star who only appears in this one event has diluted mastery value; a four- or five-star who is used in every event amortizes the investment across months. For this event, push mastery levels on your control and shift operators first and leave the carries at a sufficient level.

Modules versus skill levels

Module data blocks are the main bottleneck. My rule: unlock modules that change skill rotation first, and push pure stat modules back. A rotation-changing module alters where and when you deploy; a stat module only changes whether you kill something in two hits or three. Under a 1-HP objective, the first kind is worth more.

Arknights Directed Selection Banner Advice

Picking three of six six-stars

The pool lets you self-select three six-stars from Mon3tr, Pramanix the Prerita, Bellone, Mantra, Degenbrecherand Blaze the Igniting Spark (6-star rate: 2%). Once locked in, the only six-stars that can appear on that banner are your three picks, and together they account for 100% of the six-star rate.

That makes this a no-loss banner. Prioritize operators who fill a missing role and are unlikely to return soon. If two of your three picks are operators you already own, you are effectively lowering your own expected value.

The 60% five-star rule

On the five-star side you can pick from arknights-mitm, arknights-kichisei, arknights-surfer, arknights-paprika, arknights-cairn and arknights-ripresa (5-star rate: 8%). Five-stars you did not pick can still appear; your three selected five-stars together account for 60% of the five-star rate. That 60% figure is stated plainly in the first-party announcement, yet many players read it as 100%. The expected cost of chasing one specific five-star is higher than it looks, so do the math before committing.

Arknights Vector Breakthrough #3 FAQ

Q: When does Vector Breakthrough #3 run?
A: Stages are open September 29 16:00 to October 20 03:59; the Breakthrough Milestone continues to October 23 03:59 .

Q: What do I need to unlock the stages?
A: Clear Main Story 2-10. There is no other prerequisite, so finishing chapter two is enough.

Q: Do repeat clears still pay out?
A: Yes, but only a small amount of "Slippery Floor". The bulk comes from first clears, so repeat low floors only to close a gap.

Q: Can the Directed Selection banner give me a six-star I did not pick?
A: No. Once you pick three six-stars, only those three can appear, and they total 100% of the six-star rate.

Action checklist

1. Push Main Story to 2-10 and confirm the event stages are unlocked
2. Farm the all-day Resource Collection stages early for battle records and LMD
3. Clear Core Breakthrough floors 1-5 to unlock Special Front's first batch
4. Fill out Battle Supplies in Special Front before returning to Core Breakthrough above floor 6
5. Repeat low floors for "Slippery Floor" when stuck, rather than grinding floor 11-12
6. Double-check your three six-star picks for duplicates before pulling on Directed Selection

This guide will be revised as the event progresses. More Arknights coverage lives on GameHub.