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Furnace FC1 to FC10: every level's cost

The full climb in one table — Fire Crystal, Refined, time and what to build first.

Updated 2026-10-14 · 3 min read

The Furnace is the building everything else waits on: every other building's Fire Crystal level is capped by it, and every Furnace level has its own list of buildings that must be upgraded first. This guide lays out the full climb from level 30 to FC10 in one place — what each level costs, how the costs grow, and what you need to have built before you can start.

Every Fire Crystal level, at a glance

Each row is the whole cost of reaching that level from the one before it — all five segments added together, not just the next step the upgrade screen shows you. Meat and Wood are always the same amount, so only Meat is listed. Times are with no construction speed at all.

Why the "Requires" screen undersells it

From level 30 onwards, each Furnace level is split into five segments: FC8, then FC8-1, FC8-2, FC8-3, FC8-4, and finally FC9. The upgrade screen only ever lists the segment you're about to start. The first four segments of a level usually cost the same; the last one costs roughly half the Fire Crystal but double the Refined Fire Crystal. So when the game asks for 280 Fire Crystal for your next FC8 step, the real bill for FC9 is 1,260 Fire Crystal and 180 Refined.

Where Refined Fire Crystal comes in

Up to FC5 everything is paid in plain Fire Crystal. Refined Fire Crystal appears in the very first segment after FC5, and from there it's the real bottleneck: FC5 → FC6 needs 60 Refined, while FC9 → FC10 alone needs 420. Of the 5,895 Fire Crystal you spend from FC5 to FC10, every bit of Refined you'll need (870 in total) comes in the same stretch. If you're around FC5, start refining early — it's slower to stock up than Fire Crystal itself.

What to build first at each level

This list is the gate. Every Fire Crystal level of the Furnace needs the Embassy at the level below, so keeping the Embassy one step behind the Furnace avoids a stall. The second building follows a fixed rotation: Research Center for FC1, then the Lancer, Infantry and Marksman camps in turn — Lancer for FC2, FC5 and FC8, Infantry for FC3, FC6 and FC9, Marksman for FC4, FC7 and FC10. So each camp only needs to keep up every third level. The other buildings can't go above the Furnace's level, which is why a balanced plan matters more than rushing one building.

Making it faster

The times above assume no bonuses. Your construction speed divides them, and Double Time takes 20% off what's left — see construction speed explained for the exact formula and a worked example. If you start a Fire Crystal upgrade on SvS prep day 1, every Fire Crystal is worth 2,000 points and every Refined one 30,000 — more in the SvS prep plan.

Try it with your numbers

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