PURIFICATION NODE: SEWAGE TO XIRCON ANALYSIS | ENDFIELD
Table of Contents
The latest Arknights: Endfield patch dropped a new toy into the Test Area Site, and the factory community has been arguing about it ever since. The Purification Node sits quietly across the map from your Wuling PAC, converting sewage into Xircon precursor at a punishing 30:1 ratio, daring you to lay enough pipe to justify the protocol cost.
Is it worth the underground pipes, the manifold conduits, and the protocol slots you’d have to tear out of your existing build? Or is it an aesthetic placeholder for whatever the devs are cooking up two patches from now? After digging through community math, factory layouts, and a few absolutely unhinged pipe runs that span half the map, here is the most complete breakdown of the Purification Node you’ll find — what it does, how it works, why it might disappoint you, and how to extract value from it if you’re determined to use it.
TL;DR - Key Points
- 30 Sewage → 1 Xircon Effluent — punishing conversion ratio, max ~12 Effluent/min at Level 4
- Located in Test Area Site, far from any AIC — needs underground pipes or 5-15 manifold conduit pairs to reach
- Wuling protocol capacity is the real cost — the 350-building cap forces tearing out ziplines, pylons, or relays
- Realistic gain is ~1 Heavy Xiranite per minute — assuming a spare Forge of the Sky you probably don’t have
- Bottled-sewage shuttle is the protocol-cheap workaround — you become the conveyor belt
- Multiple unused acid pools nearby — strong evidence the Node is setup for a future patch
- Verdict: skip unless you enjoy the puzzle — revisit when (or if) a third AIC lands near the Test Area
What the Purification Node Actually Does
The Purification Node is a world facility added in the latest patch, parked in the Test Area Site across the map from the Wuling PAC. Its single job is converting Sewage into Xircon Effluent, the precursor liquid that feeds Heavy Xiranite and SC Wuling Battery production — two of the highest-value endgame resources in Endfield.
The headline number is the conversion ratio: 30 Sewage in, 1 Xircon Effluent out. At max tier (Level 4, the current cap), the node accepts up to 6 units of sewage per second through three inlet conduits, theoretically producing ~12 Xircon Effluent per minute. That theoretical maximum assumes you can actually deliver 360 sewage per minute, which most realistic Wuling factories cannot, so expect actual output closer to 5-6 Effluent per minute.
Why does this matter? Because Xircon Effluent is one of the few resources in the game that has two meaningful downstream uses. Most factory buildings serve one production chain. The Purification Node, in theory, lets you redirect sewage waste into either your battery line or your Xiranite line depending on which is bottlenecking. In practice, the throughput is too low for that flexibility to be transformative — but the design intent is interesting and worth understanding.
That theoretical promise is also why it has been the most divisive addition in recent memory. On paper, recycling sewage waste into a precursor for two endgame resources sounds excellent. In practice, the building’s location, throughput, and infrastructure tax make it one of the most awkward installations the game has ever shipped.
Where Sewage Actually Comes From in a Modern Wuling Factory
Before deciding whether the Purification Node is worth wiring in, you need to understand where the sewage feeding it comes from — because that determines how much you can actually pipe in.
The dominant sewage source in modern Wuling builds is the Coprium refining loop. Coprium refining was overhauled two patches ago to produce significant sewage as a byproduct, and most endgame factories now generate 150-180 sewage per minute purely from this process. Before the rework, this sewage was effectively waste — you either vented it via a treatment unit or accepted the throughput loss when storage capped out.
There are smaller, secondary sources too: certain alluvium processing recipes, a handful of specialty refining chains, and the occasional overflow from buildable water treatment units. But the Coprium loop is the only one that produces enough sewage at a steady rate to feed the Purification Node meaningfully.
This is the central paradox of the Purification Node: it’s a building designed to consume the byproduct of a process that’s already in Wuling, but it’s parked across the map from where that process happens. Every drop of sewage it accepts has to travel a long way to get there.
The Core Problem: Location, Location, Location
The single biggest complaint about the Purification Node is its placement. It sits in the Test Area Site, far from both the Wuling PAC and any AIC that could feed it sewage or use its output efficiently. There are two ways to bridge the distance, and neither is cheap.
Option 1 — Underground pipes from Wuling. This is the brute-force approach: 3 to 5 stretches of underground pipework to ferry sewage to the Node, plus another full stretch back to bring Xircon Effluent home to your Heavy Xiranite forges. Underground pipes are cheap in materials but eat protocol capacity and don’t handle elevation changes well.
Option 2 — Manifold conduits. The long-range fluid transmission buildings introduced last patch. More efficient in terms of throughput preserved over distance, and far better at handling elevation than pipes. But you’ll burn 5-15 conduit pairs to bridge the Wuling-to-Test-Area distance, and each pair costs protocol slots.
Either path costs material, time, and most painfully, protocol slots — all for what is mathematically a small efficiency bump on top of your existing factory output. Both options also require a non-trivial amount of in-world building work, which players who treat Endfield as a casual progression game tend to actively resent.
The Wuling Protocol Capacity Crunch
The distance problem compounds badly with the Wuling protocol ceiling. Most players are already brushing up against the 350-building cap by the time they unlock the Purification Node, because Wuling is by far the busiest region in the game.
Here’s what a typical post-patch Wuling slot allocation looks like:
| System | Typical Slots |
|---|---|
| Mining rigs (Cuprium, Originium, Ferrium) | 30-45 |
| Conveyor logistics & belts | 60-90 |
| AIC + sub-AICs | 25-40 |
| Forges of the Sky + supporting refineries | 50-70 |
| Severe alluvium / specialty processing | 20-30 |
| Water treatment & fluid handling | 15-25 |
| Ziplines, pylons, relays, QoL | 40-60 |
| Storage, sorting, packaging | 30-50 |
Add it up and most builds sit at 270-410 slots, with the upper end already over budget. A long string of conduits to the Test Area can easily force you to dismantle existing quality-of-life infrastructure — ziplines you actually use, pylons that speed traversal, even relays that you depend on for mining throughput.
For most players this becomes a hard choice: keep the build you already have and skip the Purification Node, or strip optimizations to make room for marginal gains. The community consensus right now is overwhelmingly to skip.
The deeper irony is that the protocol capacity ceiling is itself a soft cap meant to force optimization. The Node would actually be a reasonable optimization target — if it weren’t competing for slots against the very infrastructure that lets you optimize at all.
The Math: Tier-by-Tier and Real-World Output
This is the question that decides whether the Purification Node is a feature or a footnote. Let’s lay out the actual numbers.
Theoretical Throughput by Tier
| Tier | Sewage In (max) | Xircon Effluent Out (max) |
|---|---|---|
| Level 1 | 2/sec | ~4/min |
| Level 2 | 3/sec | ~6/min |
| Level 3 | 4.5/sec | ~9/min |
| Level 4 (cap) | 6/sec | ~12/min |
Real-World Output From a Typical Wuling Factory
| Step | Value |
|---|---|
| Sewage produced by Coprium loop | 150-180/min |
| Sewage actually delivered to Node (after losses) | 150-180/min |
| Xircon Effluent output | ~5-6/min |
| Heavy Xiranite produced (1 Effluent → 1 Heavy Xiranite via forge) | ~1/min |
| Forge of the Sky required | 1 additional |
The bottom line: after the underground pipework, manifold conduits, and protocol sacrifices, the Node nets you the equivalent of one extra Heavy Xiranite per minute — assuming you have a spare Forge of the Sky to dedicate to it, which most players don’t because the 12-forge cap is already fully allocated.
For context, your factory already caps most progression resources within 3-5 days of active play without touching the Purification Node. One extra Heavy Xiranite per minute is real, but the time-to-cap improvement is small enough that you won’t notice it unless you’re tracking spreadsheets.
The “Cut Content” Theory
The most popular community theory is that the Purification Node is groundwork for a future update. A few signals point that direction, and they’re worth taking seriously because they collectively make a strong circumstantial case.
Unused acid pools. The Test Area Site has multiple infinite acid pools scattered around it that currently have no purpose. Acid is already abundant near the Marker Stone AIC, so the extra pools feel like setup for recipes that don’t exist yet. The most likely candidate is a new AIC or sub-AIC that uses acid as an input for higher-tier Xircon or Xiranite recipes.
The next confirmed region. The Integrated R&D Area near the two Originium mining nodes across the river is widely expected to introduce a third sub-AIC. If that lands, the Purification Node suddenly becomes practical — no more cross-map pipe runs — because the R&D Area sub-AIC could be the destination for both raw sewage and Xircon Effluent.
The “cut content” interpretation. A less generous theory holds that the area looks like work that was scoped down. Sewage processing may have originally been designed as a remote, dedicated facility (exactly what the Test Area Site is now), then the devs decided that piping sewage across the map as an introduction to fluid management would be miserable for new players, so they shipped buildable water treatment units in the AIC instead and left this as a hook for later.
Either reading leads to the same conclusion: the Purification Node isn’t really designed for the current patch. It’s designed for whatever’s coming next. The question is whether you want to set up infrastructure now to be ahead of the curve, or wait for the curve to arrive.
How to Actually Wire It In (If You’re Determined)
If you’ve read this far and still want to make it work, here’s the realistic approach. The community has converged on a fairly stable set of techniques, and following them will save you hours of pipe-laying frustration.
The Manifold Conduit Run (Recommended)
- Plan the route first. Walk from your Wuling PAC to the Purification Node before placing anything. Note elevation changes, water gaps, and any QoL infrastructure (ziplines, pylons) you can route around rather than through.
- Use 5-6 manifold pairs. Place pairs end-to-end with line-of-sight where possible. Manifolds handle elevation natively, so don’t be afraid to route them over terrain.
- Dedicate one return manifold pair for Xircon Effluent. Bring the Effluent back to a separating unit at your AIC, then pipe it normally to your Heavy Xiranite forges.
- Reserve protocol slots in advance. Tear out the lowest-value QoL infrastructure first (relays you don’t actively use, redundant ziplines) before placing manifolds.
Practical Tips From the Community
- Stay connected to a conduit while teleporting. This lets you cover terrain that would otherwise be impossible to pipe — water gaps, cliff drops — as long as you stay below the ~220m disconnect threshold.
- Hold ALT while building pipes (keyboard/mouse). Forces single-direction construction and extends placement reach to ~8 squares from your character. Essential for clean runs across open terrain.
- Conduits, not pipes, for elevation. Pipes hate height changes; conduits don’t care. Use conduits anywhere the terrain isn’t perfectly flat.
- Bottle-and-shuttle is the protocol-cheap alternative. Bottle sewage in your Wuling PAC with a packaging unit, manually shuttle bottles to the Test Area, unpack at the Node, and reverse the process for Xircon Effluent. Almost no protocol capacity cost, but no automation either — you are now the conveyor belt.
- Don’t oversize the inlet. The Node caps at 6 sewage/sec. Piping 12/sec just creates backpressure and wastes sewage that could be vented.
Common Mistakes Players Are Making
A few patterns have emerged from the first wave of Purification Node builds. Avoid these and you’ll save yourself hours of teardown.
Overbuilding the sewage supply. Players see “6 sewage per second” and try to feed the Node at maximum capacity, building extra Coprium refining loops just to fill it. This is backwards: the Node should consume your existing sewage waste, not justify producing more. If you’re building infrastructure specifically to feed the Node, you’ve already lost the optimization battle.
Ignoring the return trip. It’s easy to focus on getting sewage to the Node and forget that Xircon Effluent has to come back to a forge. Plan both legs of the run before placing anything; otherwise you’ll find yourself with effluent stranded across the map.
Tearing out ziplines that you actually use. Protocol pressure makes ziplines look like an easy target for dismantling. But traversal-heavy players will hate themselves an hour later when they’re back to running everywhere. Strip relays and redundant pylons first.
Not levelling the Node before committing infrastructure. A Level 1 or Level 2 Node produces a fraction of the Level 4 throughput. Level it to 4 before you build out the conduit run — otherwise you’ll find your expensive infrastructure idle most of the time.
Treating it as a priority unlock. Some players are dropping other progression activities to engage with the Node early. Don’t. Your factory will progress faster if you stay focused on the buildings that meaningfully change throughput, and revisit the Node when (or if) it becomes worth the bother.
Should You Bother? Honest Verdict by Player Type
For the current patch, the Purification Node falls into a strange middle ground: functional but not rewarding. The right answer depends entirely on what kind of player you are.
Completionists who enjoy the factory puzzle. This is exactly your kind of optional optimization. Micro-routing, manifold planning, the satisfaction of leftover sewage finally doing something productive. Go in knowing the reward is small, but the puzzle itself is the point.
Regular players focused on progression. Skip it. Your factory will cap most resources in days regardless, and the protocol capacity you’d burn on cross-map pipes is more valuable elsewhere. Come back when (or if) the next patch makes it relevant. There is no progression penalty for waiting.
Min-maxers chasing every last efficiency point. The Node theoretically pushes your factory closer to perfect resource utilization, but the gains are small enough that optimizing your Forge of the Sky allocation usually pays better than piping sewage across the map. Run the spreadsheet before committing infrastructure — in most builds, the math says no.
New endgame players still building out Wuling. Absolutely skip it for now. You have far more impactful builds to lock in first, and the Node will still be there when you’re ready.
The honest read: the Purification Node is a placeholder feature wearing the costume of an endgame mechanic. It works, it’s not broken, and it’s not useless — but it’s clearly waiting for something. Until the next update arrives with either a closer AIC or new recipes that demand Xircon Effluent at scale, it feels like a side quest you’ve been handed three patches too early.
What This Reveals About Endfield’s Design Philosophy
Stepping back, the Purification Node is a useful lens on how Endfield approaches its factory layer. The game consistently constrains you in ways that force interaction with new systems. Limited resource nodes, limited forge counts, limited protocol capacity, awkward distances. These aren’t oversights, they’re the design language.
Every patch arrives with a puzzle: given these new pieces and your existing factory, what’s the optimal configuration? That works well when the new pieces meaningfully change the puzzle. The Coprium refining loop changed it. Buildable water treatment units changed it. Manifold conduits dramatically changed it.
The Purification Node, in its current form, doesn’t quite — it adds a piece that nudges the optimum slightly without redefining it. That makes it the rare Endfield building that fails the “is this fun to engage with?” test.
Players who treat Endfield like a sandbox factory game tend to find this kind of half-finished system frustrating; players who treat it as an evolving puzzle find it exciting precisely because they expect the next patch to complete the picture. Neither group is wrong, but the Node lands very differently depending on which camp you’re in.
For what it’s worth, the devs have a track record of expanding underwhelming systems in subsequent patches. The first iteration of Wuling fluid logistics was famously rough before manifold conduits made it manageable. Hetonite was a logistical nightmare before it was tuned. The Purification Node will probably follow the same trajectory — so if you’re willing to be patient, history says it gets better.
The Watch List: What Would Change This Calculus
The Purification Node is one patch announcement away from going from skip-tier to mandatory. Here’s what to watch for in upcoming patch notes.
- A third sub-AIC near the Test Area Site. This is the single biggest factor. A closer AIC collapses the protocol capacity problem because the cross-map pipe runs disappear.
- New recipes using Xircon Effluent at scale. If a future recipe requires 30+ Effluent per minute, the Node shifts from optional optimization to mandatory infrastructure.
- Acid-input recipes appearing in any AIC. Would explain the otherwise-purposeless acid pools in the Test Area and likely tie back to the Node.
- Protocol capacity expansion. If the 350-building cap gets raised, the Node’s cost-benefit shifts dramatically in its favor.
- A new forge type or Forge of the Sky cap increase. Currently the 12-forge cap is the secondary bottleneck. Loosening it makes the extra 1 Heavy Xiranite/min from the Node directly useful.
If any one of these arrives, the players who already laid the pipework are going to look very smart very fast.
Final Read
The Purification Node is one of the most polarizing additions to the factory layer in recent memory — not because it’s bad, but because it’s clearly incomplete. It introduces a real mechanic with real output, parks it in a location that punishes the player for engaging with it, and offers rewards that don’t quite justify the engagement cost.
For now, treat it as optional content. Build it if you enjoy the puzzle, skip it if you don’t. Either way, keep an eye on the next patch — if a third AIC or new acid-based recipes drop near the Test Area Site, this entire conversation flips overnight.
Until then, the Purification Node remains the most expensive way in Arknights: Endfield to get 1 extra Heavy Xiranite per minute. Whether that’s a feature or a punchline is up to you.
Frequently Asked Questions
What does the Purification Node do? Converts Sewage into Xircon Effluent at a 30:1 ratio, with a maximum throughput of ~12 Xircon Effluent per minute at Level 4. The Xircon Effluent feeds Heavy Xiranite or SC Wuling Battery production downstream.
Where is the Purification Node located? In the Test Area Site, across the map from the Wuling PAC. Its distance from any AIC is the single biggest practical limitation of the building.
Is the Purification Node worth using right now? For most players, not yet. The output is modest, infrastructure cost is high, and the Wuling protocol capacity ceiling makes the trade-off unfavorable. It is most likely groundwork for a future patch.
What is the conversion ratio? 30 Sewage → 1 Xircon Effluent. At Level 4 the Node can intake up to 6 sewage per second, producing roughly 12 Xircon Effluent per minute at theoretical maximum.
How much Heavy Xiranite does it actually produce? In a typical Wuling factory with 150-180 sewage per minute available, the Node nets you approximately 1 extra Heavy Xiranite per minute, assuming a spare Forge of the Sky to process the Effluent.
Can I use bottled sewage instead of piping? Yes. Bottle sewage in your Wuling PAC with a packaging unit, transport bottles manually to the Test Area, and unpack at the Node. Return Xircon Effluent the same way. Avoids the protocol capacity cost but isn’t automated.
How many manifold conduits do I need to reach the Node? Between 5 and 15 manifold pairs depending on your routing and how aggressively you cut across terrain. Most efficient builds use 5-6 pairs by leveraging conduits’ ability to handle elevation.
Will the Purification Node get better in future updates? Most likely. The upcoming Integrated R&D Area is expected to introduce a third sub-AIC, and the unused acid pools near the Test Area Site strongly suggest new recipes tied to the Node are planned. Players who lay pipework now may benefit when the next patch arrives.
Should I level the Purification Node before building infrastructure? Yes. A Level 1 or Level 2 Node produces a fraction of the Level 4 throughput. Level it to 4 before committing significant pipework or manifold infrastructure — otherwise you’ll find your expensive runs idle most of the time.
Does the Purification Node work with anything other than sewage? Currently no. The Node only accepts sewage as input and only produces Xircon Effluent as output. Future recipes may expand this, but as of the current patch it is single-purpose.
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