OpenFront MIRV Guide
Flat 25M cost, global launch lockout, warhead saturation, and SAM interception — v34 rules.
A MIRV launches an unarmed carrier from a ready Missile Silo, flies to a separation point, and creates many independent nuclear warheads aimed across the selected player’s land. The carrier cannot be targeted by SAM Launchers. After separation, every MIRV warhead becomes a normal in-flight nuclear target that SAMs can intercept.
The current formal release boundary is v0.34.0-beta1. It replaces the old global price ladder with a fixed price and an asymmetric global launch cooldown.
Fixed Price and Global Launch Cooldown
Every MIRV costs a fixed 25,000,000 Gold in v34. Previous launches no longer increase the purchase price. For k planned MIRVs, the weapon budget is simply:
MIRV budget = 25,000,000 × kA successful launch instead records the launcher and starts a 600-tick, 60-second cooldown for every other player. The most recent launcher is exempt and can fire again from another ready Silo; that relaunch restarts the wait for everyone else.
Three MIRVs cost 75M and five cost 125M. Fixed pricing does not mean three teammates can launch together. After the first successful execution, only that launcher remains exempt until the global timer expires.
A teammate’s ready Silo does not inherit the exemption. Nuclear planning shifts from outbidding a rising price to deciding whether the current launcher should retain initiative.
Missile Silo Slots Control Launch Tempo
A Missile Silo costs 1,000,000 Gold and takes 100 ticks, or 10 seconds, to build under normal rules. A level-N Silo has N independent launch slots.
Every Atom Bomb, Hydrogen Bomb, or MIRV carrier occupies one slot when launched. That slot needs 90 ticks, or 9 seconds, before it is ready again.
Upgrading adds a slot; it does not shorten the 9-second cooldown. The new slot begins with its own 90-tick loading period.
Carrier Flight and Separation
The carrier flies at 15 tiles per tick. It is faster than an Atom or Hydrogen Bomb, both of which use a base speed of 10.
The carrier does not explode at the clicked location. It travels toward an intermediate separation point derived from the launch and target coordinates.
At separation, the carrier creates the center warhead plus as many valid extra targets as its search can find.
The SAM target list contains Atom Bombs, Hydrogen Bombs, and MIRV Warheads. It deliberately excludes the carrier.
Why 350 Warheads Is a Ceiling, Not a Promise
The target generator stops at 350 targets, but it stops earlier when candidate searches fail. The clicked center target is inserted first.
Every extra target must satisfy all of these conditions:
- It is a valid tile inside the map
- It is land rather than water or impassable
- It belongs to the same player who owns the clicked target
- It lies within 1,500 Euclidean tiles of the clicked target
- It stays at least 55 Manhattan tiles from every target already selected
A click near a map edge wastes part of the 1,500-tile search circle outside the playable area. A coastal click spends another large portion over water.
Fragmented ownership also reduces candidates.
Warhead Speed, Spacing, and Arrival Pattern
MIRV warheads start at 22 tiles per tick. Their order adds a speed bonus from 0 through 4, giving later groups speeds up to 26.
Each warhead waits a random 0 through 14 ticks before beginning its flight.
Targets are sorted from farther to nearer by Manhattan distance before the speed stagger is assigned. The strike is a spread in both space and time.
Each warhead has an inner blast radius of 12 tiles and an outer radius of 18.
How SAM Defense Really Works
A SAM Launcher searches candidate nukes within a broad 600-tile search radius. That is not the launcher’s real firing range.
A level-N SAM has N missile slots and uses this actual range:
SAM range = 150 - 480 / (level + 5)Level 1 reaches 70 tiles, level 5 reaches 102, level 10 reaches 118, and level 20 reaches 130.8.
Every used SAM slot reloads for 90 ticks, or 9 seconds. One SAM missile destroys one Atom, Hydrogen, or MIRV warhead.
Offensive Workflow: Prepare the Strike
Step 1: Read launcher identity and cooldown before committing
Budget 25M for each planned MIRV, then identify the most recent launcher. If it was another player, read the remaining global timer. If it was you, count other ready Silo tubes and decide whether retaining launch initiative justifies another strike.
Step 2: Inspect the target’s shape
Prefer a click deep inside a broad, continuous block of enemy land. Avoid centering over a coast, map edge, narrow peninsula, or mixed-ownership frontier.
Step 3: Count ready Silo slots
Open with separate ready Silos when simultaneous pressure matters. One high-level Silo provides parallel slots, but a recent upgrade may still be loading.
Step 4: Force a hard defensive choice
Mixing Hydrogen and MIRV pressure can change SAM target priority. The Hydrogen bonus may draw a ready missile when both trajectories qualify.
Step 5: Exploit the result immediately
Prepare troops, transports, or a second front before launch so damaged borders convert into territory gains.
Defensive Workflow: Survive the Split
Build depth, not one decorative circle.
SAM value comes from both geometry and loaded slots. Place launchers where targetable approach or terminal segments can enter real firing range.
Track cooldown queues.
After a launch, note the 9-second reload. A displayed level is not the same as the number of shots ready now.
Reduce valuable target density.
MIRV extra targets require the selected player’s land. Complex ownership, water, and narrow shapes reduce legal spacing opportunities.
Preserve the counterattack.
SAMs cannot promise zero impacts. Keep troops and routes outside the likely target area so surviving forces can reclaim scattered damage.
Common Myths Corrected
- The MIRV carrier bypassed SAM, so all warheads are safe — Wrong. The carrier is excluded, but every spawned warhead is an eligible SAM target.
- Three teammates can each fire one because all cost 25M — Wrong. The first successful launch blocks the other two teammates for 60 seconds.
- My level-5 SAM circle covers the destination — Incomplete. Level 5 has 102 range, but intercept needs a targetable trajectory point, a ready slot, and enough missile travel time.
- A level-10 SAM always stops ten warheads — Wrong. Ten is its maximum simultaneous loaded slots. Geometry and timing reduce actual shots.
Read Nukes for Atom and Hydrogen rules, SAM Defense for warship interception, and Nation Pressure for nuclear diplomacy around Hard or Impossible Nations.
Frequently Asked Questions
Quick answers to the most common OpenFront questions.
What does a MIRV cost in v34?
A flat 25,000,000 Gold. The old price ladder that rose with each launch is gone. Budget 25M per MIRV carrier you plan to fire.
How does the global launch lockout work?
A successful MIRV launch starts a 60-second cooldown for every other player. The last launcher is exempt and can fire again to restart everyone else's wait. A teammate's Silo does not bypass the lockout.
Can SAMs shoot the MIRV carrier?
No. The carrier is not in the SAM target whitelist. SAMs can engage individual MIRV warheads after separation, but not the carrier itself.
Does each MIRV always hit 350 tiles?
No. 350 is the maximum. Actual count depends on valid enemy land, spacing rules, map bounds, water, ownership, and random search. Coastal clicks, map edges, and fragmented holdings produce fewer warheads.
How many SAMs do I need to stop a MIRV?
One SAM missile destroys one warhead. A level-N SAM has N loaded slots. The pressure estimate is (eligible projectiles - ready SAM slots). Geometry, arrival order, and targetability mean this is an estimate, not a guarantee.