Furnace rush deep dive: days 1–30 and the FC wall

A longer progression guide covering Furnace gates, camp unlocks, research pacing, and what to stockpile before Fire Crystal.

Goal

Keep the Furnace as your bottleneck. Everything else — camps, research, embassy — should chase it, not leapfrog it for vanity power screenshots.

Phase map

Days 1–7 — unlock the city spine

Push Furnace to unlock troop camps (Infantry around Furnace 7; Lancer/Marksman shortly after depending on your table).
Build Embassy when Furnace 8 opens — alliance helps cut timers hard.
Open Infirmary capacity early; dying troops teach expensive lessons.

Use the building calculator with your construction speed % so “overnight” upgrades are real, not vibes.

Days 8–20 — research + camps in lockstep

Research Center (Furnace 9+) should stay within a level or two of Furnace.
Camps unlock troop tiers at milestones (4 / 7 / 11 / 13 / …). Do not starve camps while hoarding for a single Furnace jump if you need trainable tiers for events.
Save a chunk of speedups for point events (SvS prep, Alliance Showdown) instead of burning everything on Tuesday boredom.

Days 21–30 — approach the FC wall

Furnace 25→30 is where resource and time curves steepen.
Stockpile meat / wood / coal / iron with intentional gathering heroes and chests.
Skim Fire Crystal before you hit 30 so alloy/crystal sinks do not surprise you.

What not to do

Maxing decoration or side buildings far above Furnace.
Training only one troop type “because power went up.”
Ignoring hospital capacity before Bear / Castle / SvS battle days.

Resource rhythm

Gather → bank → spend into Furnace prerequisites.
Use alliance help + research speed before paid speedups.
Check chief gear and charms only after city spine is healthy — gear does not replace a missing Furnace level.

After Furnace 30

Fire Crystal stages change the upgrade language. Pair this guide with state age and Fire Crystal basics. Re-verify numbers in the client upgrade preview after major patches.