Arknights: Endfield Yazhen Syringe Blueprint Codes and Factory Setup

The Yazhen Syringe is a healing tactical in Arknights: Endfield that auto-triggers when an operator drops below 50% HP, restoring roughly 319.52 HP per second for 6 seconds with up to three uses per battle. Producing it efficiently in Wuling is the bottleneck for most players, since a single syringe line pushes past the region's early Ferrium Ore yield. A handful of community blueprints solve the layout problem, and a few small wiring details decide whether the factory actually runs at full speed.

Quick answer: Import one of the shareable blueprint codes below for your server (Asia or NA/EU), place Yazhen seedlings into the Seeding Machine, connect water pipes, and add a flow integrator at the syringe outlet so Ferrium bottles don't block the syringe path to the Protocol Stash.

Yazhen Syringe blueprint codes by server

Blueprint sharing codes are region-locked between Asia and NA/EU. Copy the code exactly, with no trailing spaces or line breaks, and paste it into the Import Blueprints screen under the Shared Blueprints tab. The letter right after EFO01 is a capital I, not a lowercase L — a common cause of import failures.

The compact Asia layout converts to Jincao Tea by changing the flower selected in the middle unloader, so one footprint can swap between the two healing tacticals depending on which side base wants what.

What the Yazhen Syringe does in combat

Equipped as a tactical, the syringe activates automatically on any operator whose HP falls under 50%, up to three times per mission. Uses refresh after the charge is depleted, and it can also be sold at the Sky King Flats Construction Site outpost for 16 Stock Bills per unit, which makes it a steady source of currency alongside its battlefield role.

The [C] variant restores 319.52 HP/s for 6 seconds. Higher tiers (such as [A]) share the same production chain and swap in when you unlock better recipes in the Tangtang update era content.

Recipe and throughput

The base recipe for the Yazhen Syringe [C] at the AIC Factory Facility runs on a 10-second cycle and consumes plant powder and Ferrium bottle inputs to output syringes. The shredder produces two powders per Yazhen flower while the reactor only consumes one per cycle, which is why most blueprints route the extra powder back to the depot or through a second Protocol Stash.

Because early Wuling mining purity is low, one full syringe factory will overrun Ferrium supply. Transferring about 1,500 extra Ferrium Ore from Valley IV through Megastorage adds roughly 25/min, which narrows the gap but does not close it entirely. Running the line slightly under cap until purity improves is the realistic baseline.

The two wiring fixes that matter

Most import failures on this blueprint aren't the code — they're the belt and pipe configuration at the outlet.

Step 1: Place a flow integrator at the syringe outlet. Without it, Ferrium bottles travel into the Protocol Stash instead of the syringes, and the finished product stops reaching storage.

Step 2: Add a belt bridge where the syringe belt and Ferrium bottle belt cross. If the two belts merge at the intersection, bottles get pulled off course and block the stash input.

Step 3: Manually add fluid pipes after pasting. Pipes do not copy over with the blueprint code, so water routing to the Seeding Machine and any liquid output lines must be reconnected by hand.

Step 4: Drop a Yazhen seedling into the Seeding Machine to start the plant farm cycle. The self-sufficient 19×17 layout loops sandleaf/Yazhen plantation output back into the shredder without touching main inventory.

Why two Protocol Stashes appear in some builds

If one stash fills with a single item, it blocks other items sharing that stash even if capacity remains elsewhere. Splitting shredded Yazhen powder (the unused second powder) into its own Protocol Stash prevents that lockout and keeps the main syringe output flowing. It's a deliberate design choice in the compact builds, not a mistake.

Pulling plants from the main inventory instead of running a closed plant loop is similarly intentional in Wuling. The region's depot can be accessed from both sides of a depot building, which roughly doubles effective throughput versus Valley 4 and makes flat, modular factories more space-efficient than all-in-one loops.

Common import mistakes

• Extra space or newline at the end of the pasted code — the import silently fails.
• Reading the capital I as a lowercase l when typing the code manually on console.
• Using an Asia code on NA/EU or vice versa — codes are not cross-region compatible.
• Pasting against the edge of the AIC area when parts of the blueprint legitimately extend outside it. Sliding the buildings inward after import, or trimming one pipe section, usually resolves the placement error.

Verifying the factory works

Within one full 10-second cycle after starting, you should see syringes arriving at the primary Protocol Stash and Ferrium bottles routing separately without backing up on the belt. If the stash is receiving only bottles, the flow integrator is missing or misplaced. If nothing moves, check that water pipes were manually connected to the Seeding Machine and that a Yazhen plant is seated in the seeder.

Once the line is stable, the syringes can be fed directly to the Sky King Flats Construction Site trade for Stock Bills, or stocked for combat use. Building a second syringe line, armor materials, or a Jincao drink production line on top of the first is only realistic after Ferrium purity improves or after you divert ore from non-critical amethyst production.