Unlocking Tier 5 in Sandustry is not a single task. The Tier 4 to Tier 5 transition has two separate gates that both have to close before the next factory level opens. One is an exploration step that sends you underground to investigate an Anomaly, and the other is a production step that asks you to make Florinol. Miss either one and Tier 5 stays locked, even if the other side is finished.
Quick answer: Follow the Tier 4 objective underground and investigate the Anomaly (this also unlocks the Void Touched achievement), then build the Amethelis to Florinol chain and produce enough Florinol to satisfy the production gate. When both requirements are met, Tier 5 unlocks.
What you need before you reach the Tier 5 gate
By the time Tier 4 sends you toward the Anomaly, your factory should already be producing Amethelis from the flower stage. The Florinol side of the gate builds directly on that output, so the important preparation is research rather than new raw materials.
The core unlock for the production gate is Drying & Condensing, which gives you the Steam Dryer and the Condenser. Those two machines turn the middle of the Florinol chain into a working process. The Florinol Battery from Tier 5 research stores the finished liquid as Energy, which matters immediately after the gate closes.
| Research | Tier | What it unlocks |
|---|---|---|
| Drying & Condensing | Tier 4 | Steam Dryer for drying materials with Steam, and the Condenser for turning gases into liquids using Snow |
| Corraller | Tier 4 | Optional exploration help for capturing critters along the underground route |
| Florinol Battery | Tier 5 | Stores Florinol as Energy once Tier 5 is open |
Investigate the Anomaly (the exploration gate)
Tier 4 changes the rhythm of the game. Instead of asking for another larger production module, it points you away from the factory and underground through the Anomaly progression. This is the exploration half of the Tier 5 gate, and it is the step that awards the Void Touched achievement for investigating an Anomaly.
Note: The exploration gate cares only that the Anomaly investigation takes place. You do not need to fully clear the underground or find every Artifact to close this half.
Build the Florinol chain (the production gate)
The second half of the gate is a production target measured in Florinol. Florinol sits at the end of a short chemistry chain that starts from the Amethelis your flower stage already makes. The full path runs Amethelis to Dry Amethelis to Florin to Florinol.
The complete sequence looks like this:
Amethelis -> (Steam) Dry Amethelis -> (Heat) Florin (Gas) -> (Cold/Snow) Florinol (Liquid)Keep this line reliable rather than pretty. If your existing factory already feeds into a chain that ends in Florinol, let it run and produce toward the target instead of rebuilding earlier stages.
Why Tier 5 stays locked after you think you are done
The Tier 4 to Tier 5 handoff is one of the easiest places to misread progress, because the two gates are independent. Finishing one does not display the other as incomplete in an obvious way, so it is common to assume Tier 5 is bugged when it is simply waiting on the second requirement.
When Tier 5 refuses to open, check the two sides separately instead of guessing:
- If you completed the underground trip but Tier 5 is still locked, your Florinol production is likely short. Fix the failing conversion in the chain rather than exploring again.
- If you have been making Florinol but Tier 5 has not opened, the exploration gate is probably unfinished. Return to the Anomaly route and complete the investigation, then any remaining objective steps.
Adding more Condensers blindly or wandering the map at random both waste time. Confirm which gate is open and which one is not, then close the missing one directly.
How to confirm Tier 5 unlocked and what changes next
When both gates close, your Factory Level advances to Tier 5 and a much larger section of the Tech Tree becomes available. The clearest confirmation is the objective itself changing. The next large-scale target switches to reaching a peak of 100,000 Energy, which signals that the game has handed control from your old production stages to the Energy system.
At that point the Florinol you were building for the gate has a new job. Placed into a Florinol Battery, it stores as Energy and feeds the peak-Energy objective. The question shifts from making more of every earlier resource to finding what is preventing stored Energy from climbing.
Tip: Do not clear the new Tier 5 research all at once. Buy machines only when they help the Energy system move toward the 100,000 peak. If stored Energy is already rising steadily, let the working setup run before spending on unrelated branches.
Once you understand that Tier 5 is really two locks and not one, the transition becomes predictable. Investigate the Anomaly to clear the exploration side, run the Amethelis to Florinol chain to clear the production side, and the moment both are satisfied the next factory tier opens on its own.
