OpenFront Building Tiers

This list ranks structures, not maps. For continents versus islands versus compact versus impassable boards, use the map archetype list. For the philosophy behind S–D, start at the Tier List Hub. Exact gold steps are in gold costs. Placement and upgrade prose lives in buildings; weapon math lives in nukes.

City is the only building we treat as always S-tier. Everything else is a context call.

S-tier: City, every lobby

Each City level adds 250,000 to troop cap. Costs follow 125k, 250k, 500k, then 1M. That formula is independent of Port and Factory, so your first City is never made more expensive by a coastal start. Troop growth peaks near 42% of cap; if the bar is pinned near full, a City is usually a better click than another attack into mountains.

Build Cities when:

• The troop bar keeps filling during quiet windows.
• You are about to fight on highlands or mountains and need a larger reserve.
• A team partner is already covering navy, so your gold should raise the shared cap.

Skip a City only when you are about to die on the current cap, or when a 50k Defense Post on a choke will save more troops than +250k max that you cannot grow into. That skip is rare.

A / S situational: Port versus Factory

Port and Factory share one cost counter. The first of either type is 125k; the second in the pair is 250k, then 500k, then 1M, regardless of which type you pick. Buying Port then Factory is not two cheap 125k buildings.

Port rises to S when:

• You spawn on water you can actually hold (Oceania, Japan, Britannia, Irish Sea, Gulf of St Lawrence, Las Vegas Strip).
• You need Trade Ships or Warships. Warships cost 250k, then 500k, then up to 1M, and they need a Port in that water.
• The win path is coastal enclosure rather than a rail spine.

Factory rises to S when:

• The landmass is compact or continental (Europe, France, Germany, United States, China, Pangaea) and trains will reach Cities.
• You already have a City or Port that can act as a paying stop — the Factory itself is not a paying stop.
• Navy is someone else’s job in a team lobby.

Factory falls toward C on scattered islands until you own a rail that actually runs. Port falls toward C on a landlocked highland spawn with no reachable sea. Do not copy a World FFA Port-first opener onto Deglaciated Antarctica and expect the same return.

See naval play when the Port call is close, and team games when one player should be the navy specialist.

A-tier on chokes: Defense Post

Defense Posts cost 50k, then +50k per post, capped at 250k. Range is 30 tiles. They do not stack on the same tile, and they are destroyed on capture rather than transferring. That last rule is why a 250k fifth post on a tile you expect to lose is a D-tier purchase even though the first 50k post is often A or S.

Place Posts on:

• Mountain passes and highland funnels.
• The one land approach to your core Cities.
• A Ranked 2v2 assigned lane where your partner cannot rotate.

Do not sprinkle Posts on a moving FFA front. The aura is wasted if the border walks off the 30-tile circle. Plains are cheaper to take than highlands, and mountains are slower still; a Post on a mountain choke multiplies an already expensive tile.

Silo versus SAM is a timing tier, not a flavor tier

Missile Silos cost 1M each. Atom Bombs cost 750k, Hydrogen Bombs 5M, MIRVs 25M + 15M × n (n = MIRVs already fired in the match). The smallest complete Atom plan from zero gold is 1.75M. A Silo with no ammo is B at best and D if it delayed a City.

SAM Launchers cost 1.5M, then 3M. In v33, MIRV warheads fly as real nukes and are interceptable. Starting a 30-second SAM after the missile warning is often too late. SAM is C while nobody has a Silo, A the moment you see the first 1M spend, and S in teams if the enemy bank can print a Hydrogen Bomb.

Practical race:

1. If you will nuke, bank 1.75M before you click Silo, unless a partner is funding the Atom.
2. If they will nuke, start SAM while they are still saving — not after the launch.
3. Hydro at 5M beats a single cheap SAM if you cannot also contest land share. Two SAMs at 1.5M + 3M is 4.5M, still cheaper than one Hydro, but only if they finish before impact.

Full yield and intercept notes: nukes. Patch context: v33.

Quick reference by lobby

Structure	FFA default	Teams	Islands / water
City	S	S	S
Port	A, S if you own the sea	A, S on a navy role	S
Factory	A inland	A if trains connect	C until a rail exists
Defense Post	A on one choke	S on assigned lanes	B unless a land bridge
Missile Silo	B until 1.75M is real	A with a shared bank	B
SAM Launcher	A after enemy Silo	S vs coordinated nukes	B

Warships are not buildings, but they ride the Port decision: 250k / 500k / up to 1M, with v33 veterancy if they live. Treat a first Warship as an A-tier follow-up on water, not a substitute for the City you skipped.

After you pick a structure from this table, confirm the map still wants it on map archetypes, then spend against the live numbers in gold costs. Placement details stay in buildings; if the next click is a nuke, switch to nukes instead of forcing another Factory.