All Six Buildings — Costs, Effects, Placement

There are only six buildings, but costs escalate as you build and a few hidden rules will cost you if you do not know them.

Cost table

Building	1st	2nd	3rd	After	Build time	Upgradeable
City 1	125K	250K	500K	1M cap	2s	yes
Factory 2	125K	250K	500K	1M cap	2s	yes
Port 3	125K	250K	500K	1M cap	5s	yes
Defense Post 4	50K	100K	150K	250K cap	5s	no
Missile Silo 5	1M	1M	1M	1M flat	10s	yes
SAM Launcher 6	1.5M	3M	3M	3M cap	30s	yes

The formulas (n = how many you already have):

• City / Port / Factory — min(1,000,000, 2ⁿ × 125,000)
• Defense Post — min(250,000, (n+1) × 50,000)
• SAM — min(3,000,000, (n+1) × 1,500,000)

Two traps you must know

Ports and factories share a counter

Build three ports and your first factory is already priced as the fourth building (1M). It works both ways. Expanding ports without a plan makes the switch to a factory economy brutally expensive.

Every building needs 15 tiles of clearance

And clicking within 15 tiles of a same-type building upgrades it instead of building a new one.

• You cannot pack cities tightly, so reserve safe interior space early
• For a new building, click somewhere clearly separated
• Sometimes upgrading is cheaper than building. Past the fourth city everything is 1M flat, so compare

Building by building

🏙 City — the top priority

Raises your troop cap by +250,000 per level. Also acts as a train station.

1,000 tiles contribute about 226,000 to your cap; one city level gives 250,000. Once expansion slows, cities dominate.

Build them deep inland. Buildings transfer with territory — a border city is a gift.

→ How Many Cities Should You Build?

⚓ Port — distance is everything

Spawns trade ships that pay both sides. Required for warships, and transport boats launch from here.

Trade income is an S-curve with its inflection at 300. Distance 200 pays 13,557; distance 400 pays 91,443 — almost the entire payoff lives between 200 and 400.

Attacking or being attacked by a player suspends trade with them for 5 minutes.

→ Where Should You Build Ports?

🏭 Factory — needs neighbors to pay

Automatically lays rail to nearby cities, ports and factories. Trains pay gold for each building they pass.

Building owner	Gold per building
Ally	35,000
Teammate / third party	25,000
Your own	10,000

Routing through other people’s buildings pays 2.5–3.5×. Factory economies explode when you are on good terms with neighbors. Station range is 15–110 tiles.

🛡 Defense Post — best value in the game

Enemies attacking your territory within 30 tiles suffer ×5 losses and advance ×3 slower.

• Protected borders show a checkered pattern
• Not upgradeable, and overlapping posts do not stack
• Put them on chokepoints. Scattering them across open plains is waste

→ Defense Post Range and Placement

🚀 Missile Silo

Nukes launch from the nearest silo and land where you clicked. Flat 1,000,000, 9-second reload, upgradeable to reload faster.

Default targeting range is 150 tiles. Site it so targets are in range but you sit outside enemy SAM coverage.

🛰 SAM Launcher

Intercepts incoming missiles. Range is 150 − 480/(level+5) — level 1 is 70 tiles, approaching 150 asymptotically.

It does target atom bombs, hydrogen bombs and MIRV warheads. What it cannot catch is the MIRV carrier before it splits — and with a 9-second reload it cannot handle a simultaneous warhead salvo. Construction takes 30 seconds, so building one after you see the launch is too late.

→ When to Use Nukes

Suggested build order

1. First city (125K) — inland
2. Port if you have coast and can get real distance
3. Cities 2–4 — mind the 15-tile spacing
4. Defense post on your weak chokepoint
5. Factory once neighbor buildings are in range
6. Silo / SAM — late

One atom bomb costs 750,000 — six cities. Gold spent on nukes early comes straight back as falling behind.