OpenFront No-Man's-Land Fallout: What a Nuke Scar Actually Does to Your Game

Direct answer: a nuke scar is a permanent map mutation, not a one-time blow

When a nuke detonates in OpenFront, the crater is not just a troop exchange that resolves in a few seconds and then forgets. The blast writes a persistent terrain state — fallout — onto the tiles it covers, and that state silently changes two of the most important numbers in the rest of the match: the cost of retaking the scarred tiles and the threshold you must reach to win. A detonated nuke therefore buys three things at once, and you should decide whether all three of them serve your plan before you spend the gold. The first is the obvious one, the immediate troop damage from the blast radius. The second is a retake tax: every irradiated tile carries a falloutDefenseModifier, and attacking it costs that many times more troops and is slower to capture, which means a scar is much harder to take back than it was to create. The third is a win-threshold shrink: because the game measures victory as a share of non-fallout land, every irradiated tile is removed from the denominator, so the pie you must slice gets smaller the more of the map you irradiate. None of the existing nuke guides — the one on choosing a weapon, the one on defending against a strike, or the one on water nukes — walks through these three effects together, and that is the gap this page fills. The single most important thing to internalize is that the scar is permanent for the duration of the match: there is no decay timer, no cleanup, no repair. A single Hydrogen can freeze a sector for minutes, and the community calls that frozen sector a “no man’s land” for exactly this reason. So the practical answer to “what does a nuke scar actually do” is: it rewrites the retake cost of that land, it rewrites the land you must own to win, and it does both of them permanently. Treat a nuke as a map-editing tool, not as a bigger bomb, and you will stop overpaying for territory it was never meant to hand you. The three effects are also three different levers, and a good call uses all three at once rather than one in isolation: the immediate damage decides whether the strike lands at all, the retake tax decides whether the scar you create is worth holding, and the win-threshold shrink decides whether the scar changes the end of the match. A strike that only produces the first effect is a tactical bomb; a strike that produces all three is a strategic one, and the difference is exactly what separates a nuke you should fire from a nuke you should save.

Version boundary: what v0.34.22 actually documents

Everything in this guide is read from the v0.34.22 tag of the OpenFrontIO repository, which is commit 4e83752 dated 2026-10-01. That is the version boundary you should trust. The release immediately after it, v0.34.23, published 2026-10-05, is a graphics-crash recovery fix and contains no gameplay-balance change to the nuclear or fallout systems, so the effective player-facing rules described here are unchanged between the two. The upstream main branch is further ahead and has unreleased changes to other systems, but those do not touch falloutDefenseModifier, the win-check denominator, the blast radii, or the Doomsday rot, so anchoring to the v0.34.22 tag is both safe and complete for this topic. Three specific facts that are version-sensitive are worth stating explicitly so you know exactly which release they were verified against. First, the retake multiplier formula 5 - 2 x globalFalloutRatio is a v0.34.x expression; older releases used a different damage scaling for the hydrogen bomb, which is why the community is still discussing how that damage is calculated. Second, the win threshold base of 0.80 (eighty percent) with the non-fallout denominator is the current rule; an earlier release described in a community thread as “does radiation count towards winning” was the trigger that made the denominator change visible to players. Third, the Doomsday Clock “rot” that stamps tiles to nobody with fallout is the current endgame behavior, and it is what lets a map accumulate no-man’s-land with no player firing a nuke at all. If you are reading a guide that quotes an older release number for the hydrogen damage or for the win percentage, treat that figure as superseded by what is on this page. The version boundary matters here specifically because the fallout mechanic is one of the few systems where a small formula change between releases meaningfully changes the strategy, and the difference between “the first strike is the worst” and “the last strike is the worst” is entirely a function of this multiplier. This also means the boundary is a useful tool when you are watching a match: if the game client you are on predates v0.34.22, the retake tax you feel on a scar may be slightly different from the one this guide describes, so when you compare your in-game experience to the numbers here, first confirm the client release in the corner of the screen. The practical rule is to anchor any in-game observation to the client release you are actually running, and to treat a mismatch between what you felt and what this page says as a version question before a strategy question, because a stale client is the most common reason a scar feels either cheaper or more expensive than the table below predicts.

The fallout zone and the 3-5x retake tax

The core mechanic is a single function in the configuration: falloutDefenseModifier returns Math.max(0, 5 - 2 * globalFalloutRatio), where the global fallout ratio is the share of the map that is already covered in fallout. That function is applied multiplicatively to the troop magnitude and the tile cost when an army attacks a tile that has fallout. The result is that an attacked irradiated tile costs between three and five times more troops to retake than the same tile on a clean map, and it is also slower to capture. The counterintuitive part is the direction of the scaling: the multiplier is highest when the map is least irradiated. The very first nuke on a clean map imposes a 5x penalty, because the global fallout ratio is still near zero. As more of the map becomes irradiated and the ratio climbs toward one, the multiplier relaxes toward 3x. In other words, fallout is worst right after the first strike, not after the last. This inverts a common intuition: players often assume the last nuke is the most punishing because it lands on an already-scarred map, but the code says the opposite — the first scar is the most expensive for anyone trying to cross it. The strategic consequence is that the player who fires first gets to define the most expensive no-man’s-land, and every subsequent scar is marginally cheaper to retake. There is also a floor of zero, so the multiplier never drops below 3x in practice (it would only hit zero if the ratio exceeded 2.5, which cannot happen on a real map). Because the tax is applied to the attacker, the defender benefits passively: a scar you created is a defensive asset you do not have to actively hold. This is why a small scar on a contested border can be worth more than a large army parked next to it — the scar itself is the wall, and it costs the attacker five times the normal price to come over it. The which nuke to commit guide covers the blast damage and the SAM interaction; this section covers what remains after the blast is done, and it is the part most players miss. Because the tax is applied to the attacker and not to the defender, there is a second subtle ordering effect: the multiplier is the same whether the attacking army is large or small, so a retake of a single scarred tile costs five times the troops of a single clean tile, and a retake of a scarred corridor costs five times the troops of the same corridor clean, with no discount for volume. This means the scar does not favor the player who sends one big army over the one who sends many small ones, and it does not favor the small army over the big one either, because the multiplier multiplies the magnitude of whatever army arrives. The only thing that changes the math is the global fallout ratio, which drifts upward as more of the map is irradiated, so the tax you feel on a second scar is slightly lower than on the first. The practical consequence is that a scar is best created when you want the tax to be at its maximum, which is exactly the first-strike timing: fire the nuke early, on a map that is still clean, and the exclusion zone you create is the most expensive one available for the rest of the match.

The win threshold shrinks: 80 percent of non-fallout land

The win check is the second number a nuke scar changes, and it is the one players most often get wrong. The code computes numTilesWithoutFallout = numLandTiles - numTilesWithFallout, and then checks tilesOwned * 100 > numTilesWithoutFallout * percentageTilesOwnedToWin(timeElapsed). The base percentageTilesOwnedToWin is 0.80, so the rule in plain language is: you win when you own more than 80 percent of the land that is not in fallout. The critical word is not. Every tile a nuke irradiated is subtracted from the denominator before the threshold is applied, so a large Hydrogen scar does not just make the scarred area expensive to retake — it removes area from the board you must dominate. If a map has one hundred land tiles and a Hydrogen scar irradiates twenty of them, the denominator drops from one hundred to eighty, and you now only need to own a little more than sixty-four of those eighty to win, instead of a little more than eighty of the original hundred. The scar therefore lowers the absolute number of tiles you must control, which is precisely what the top community question, “does radiation count towards winning the map?”, is circling. The answer is that radiation excludes itself from the denominator: irradiated land does not need to be owned by anyone, it simply stops counting as part of the board you are trying to fill. This has two strategic readings. As an attacker, a large scar helps you win by shrinking the pie, so a nuke is not only a weapon but a way to lower the win bar for your own remaining territory. As a defender, an opponent who nukes the map is also shrinking your denominator, which can actually make it easier for you to reach 80 percent of what is left if you already hold a dense core. The net effect depends on who holds the land adjacent to the scar, which is why the threshold question cannot be answered in the abstract and must be evaluated against your current territory map. In a frozen late game this is the single most important number to keep in your head. A useful habit is to do the denominator arithmetic out loud the moment a scar appears, because the raw tile counter on the screen is the most misleading number in the late game: it still shows the total land owned, not the land that counts. If the counter says you hold sixty tiles and the map has one hundred, you might think you are at the sixty percent you need, but once the scar removes twenty tiles the real question is whether you hold more than eighty percent of the remaining eighty, which is a completely different answer. The denominator arithmetic is the only honest way to track a frozen endgame, and it is the reason the community keeps asking whether radiation counts towards winning: the counter on screen does not answer that question, but the denominator does.

Blast radii and how much no-man’s-land each nuke buys

The amount of no-man’s-land a detonation creates is set by the blast radius, which is a pair of numbers in the configuration: an inner radius and an outer radius. The three nukes differ dramatically in how much scar they buy. The MIRV carries many small warheads, each with an inner radius of 12 and an outer radius of 18, so a full MIRV spread creates many separate, relatively small scars rather than one giant one; the pattern matters more than the total. The Atom has an inner radius of 12 and an outer radius of 30, which makes it the best tool for carving a clean, round scar over a single city or a contested border corridor. The Hydrogen is the extreme case with an inner radius of 80 and an outer radius of 100, a footprint so large that it can turn a whole region of the map into no-man’s-land in a single detonation. The default detonation mode converts the blasted land to fallout via the nuke execution writing setFallout(true), so every default nuke leaves a scar; the water-nuke option is the one branch that instead converts the land to water, which is a different and permanent terrain change covered in the water nukes guide. The practical read of the radii table is that the scar area is proportional to the square of the radius, so the Hydrogen’s 80/100 footprint produces roughly a hundred times the scar area of the Atom’s 12/30 inner circle — a difference that turns a tactical denial into a map-level event. When you are choosing a nuke specifically to create no-man’s-land, you are choosing based on how large a permanent exclusion zone you want, and that is a very different calculation from choosing a nuke to destroy a single building. The MIRV’s many small scars are best for denying a wide front piecemeal, the Atom is best for a precise exclusion around one objective, and the Hydrogen is best for ending the argument over a whole sector. The radii also determine which adjacent tiles become “contested” and therefore which armies will walk into the retake tax, so the radius is really the boundary of the 3-5x multiplier zone. A practical way to think about the radius is as a no-fly circle: inside it, every army pays the tax, and the size of that circle is what decides whether a scar is a local inconvenience or a map-level exclusion. The MIRV’s many small circles let you deny a whole front at once, the Atom’s single round circle is ideal for one objective, and the Hydrogen’s giant circle is the tool that ends the argument over a region.

Nothing decays: a scar lasts until conquered or water-converted

The least intuitive and the most strategically important fact about the fallout zone is that nothing removes it on its own. A search of the entire core for a falloutDuration, a decay timer, or any cleanup routine returns nothing; the only code paths that write setFallout(false) are a successful conquest and a water nuke converting the land. A conquest happens when an army arrives on a tile that has no structures and no defending army, and that single event clears the fallout from that one tile. A water nuke clears it by replacing the land with water. Apart from those two writers, an irradiated tile stays irradiated for the entire rest of the match. This is what separates a nuke scar from an ordinary battlefield. A normal fight leaves a spent, recoverable area where troops can reposition and the front can be redrawn. A nuke scar leaves a permanent exclusion zone that stays at its 3-5x retake cost until someone physically walks across it and conquers it tile by tile. The consequence is that a scar is a durable asset: the minutes it takes an opponent to clear a Hydrogen scar are minutes in which that sector is effectively yours. This is why the community phrase “no man’s-land” is deliberate — the zone is not a temporary handicap, it is a standing condition of the map for the rest of the game. It also explains why a single well-placed nuke can end an argument over a border that has been contested for minutes: the scar raises the cost of re-crossing so high that the status quo freezes. The Doomsday Clock then introduces a second, self-propagating source of the same zone. Its “rot” relinquishes tiles to nobody and stamps them with fallout, so a map can accumulate no-man’s-land without any player firing a single nuke, and that rot-zone is excluded from the win denominator in exactly the same way as a blast scar. When the Doomsday Clock is active, the two sources of no-man’s-land — blast scars and rot — compound, and the only way to stop the compounding is to conquer the tiles faster than they rot. That race is the central decision of a Doomsday Clock endgame, and it is the second scenario below. A useful mental model is that the Doomsday Clock turns the map into a draining container: the rot is the drain, your conquest is the inflow, and the moment the drain is faster than the inflow the board starts to empty from under you, which is why the clock endgame is the one where waiting is actively punished instead of merely suboptimal.

Scenario one: denying a sector in a one-versus-one with one Hydrogen

Let us put numbers on the mechanic. Assume a one-versus-one on a map with one hundred land tiles. Both players hold roughly fifty tiles each and are contesting a border corridor about twenty tiles wide. You have saved 5,000,000 gold, the cost of one Hydrogen, and your objective is to stop the opponent from pushing through that corridor to take your capital. The decision is whether to spend the Hydrogen on the corridor or to hold it in reserve. If you fire the Hydrogen at the middle of the corridor, the 80/100 blast irradiates a large chunk of the contested land and the tiles beyond it. Assume the scar irradiates twenty of the map’s hundred tiles. The immediate effect is twofold. First, the retake tax: the corridor is now a no-man’s-land, and any army the opponent sends across it pays the falloutDefenseModifier. Because the map is only now becoming irradiated, the global fallout ratio is still low, so the multiplier is close to the 5x maximum — the opponent’s crossing is now five times more expensive than it was before, and the corridor is effectively closed for the rest of the match unless the opponent is willing to pay five times the troops to cross it. Second, the win threshold: the denominator drops from one hundred to eighty non-fallout tiles, so the player who now holds the dense core of the remaining eighty only needs a little more than sixty-four tiles to win, and if you hold a clean sixty of those, you are already at the win line. The scenario’s decision point is the opportunity cost of the 5,000,000: by spending it you gave up a future nuke and the gold it represented, in exchange for a permanent sector denial and a lowered win bar. The correct call is to fire it when your alternative is losing the capital through the corridor, because a permanent denial plus a lowered win threshold is worth more than a reserve nuke you may never get to use. The failure mode is firing the Hydrogen into water or into land you already fully control, where the scar buys you nothing and you have simply converted 5,000,000 of gold into a scar with no strategic payoff. The repeatable rule is: fire the Hydrogen at contested land you want to exclude, not at land you already own. When you do, the scar converts your gold into a permanent map mutation that your opponent must either retake at 3-5x cost or accept a smaller win threshold, and that exchange is the entire strategic payoff of the weapon.

Scenario two: the Doomsday Clock rots a stalemate into no-man’s-land

The second scenario is the one where no player fires a nuke at all. Suppose a one-versus-one has reached the Doomsday Clock endgame and the map is stuck: neither player can break the other’s core, and the front is a frozen stalemate. The Doomsday Clock “rot” now begins relinquishing tiles to nobody and stamping them with fallout. Every tile that rots is removed from both players’ holdings and, because it now carries fallout, is also removed from the win denominator. The strategic picture changes completely: the map is literally shrinking, and the two sources of no-man’s-land — the rot and any blast scars — are compounding. The player who cannot conquer tiles faster than they rot is slowly losing the board, not because the opponent is taking them, but because the tiles are simply ceasing to exist as controllable land. The decision here is a clearing race: you must push armies onto the rotting front and conquer tiles before they stamp with fallout, or convert the contested band with a water nuke to stop the rot from spreading there. The numbers matter. If the rot is clearing five tiles per minute and your conquest rate is three tiles per minute, you are losing the net two tiles per minute, and the denominator is shrinking against you. The countermeasure is to concentrate on a narrow front so your conquest rate per tile is high, rather than spreading thin. A MIRV spread of small scars can also be used offensively here: by irradiating the opponent’s clearing front, you raise their retake tax and slow their conquest rate, converting your defensive scar into a tool that wins the race. The failure mode is the player who keeps the army in reserve “just in case” while the rot shrinks the board; the scar and the rot both compound the longer you wait, and the win threshold measured against a shrinking denominator punishes inaction. The repeatable rule is: in a Doomsday Clock stalemate, the map is the enemy, and the only way to win is to conquer faster than the rot, so the correct call is always to commit to a narrow clearing front. This is the decision the nuclear stalemate breaker guide addresses from the attacker’s side; this section addresses it from the map-shrinkage side. The two perspectives matter because they point at opposite levers: the attacker’s perspective asks “which nuke breaks this core fastest”, while the map-shrinkage perspective asks “am I clearing tiles fast enough to outrun the rot”, and a strong endgame answer uses both at the same time, committing to the clearing race while choosing the single best nuke to convert the opponent’s front into a scar that slows them down.

Failure modes, countermeasures, and mode and map adjustments

The most common failure is treating the fallout zone as a one-time damage event and forgetting that it is a permanent retake tax. Players who fire a nuke and then immediately try to recapture their own scarred land pay the 3-5x multiplier against themselves, so the scar they meant as a denial becomes a trap for their own army. The countermeasure is to treat a scar you created as a wall you do not cross: the defender benefits passively, so leave the scar in place and hold the clean land behind it. A second failure is misreading the win threshold: because the scar removes tiles from the denominator, a player who is losing on raw tile count can still be close to the win line once the scar is subtracted, and a player who is winning on raw count can find the win bar drop below their holding if the opponent nukes widely. The countermeasure is to recompute tilesOwned / non-fallout tiles after every nuke, not to track raw tile count. A third failure is firing a nuke at land you already fully control, which converts gold into a scar with no strategic payoff and lowers the win bar for your own dense core without denying anything to the opponent. The countermeasure is the opportunity-cost rule from the first scenario: only fire at contested land you want to exclude. Mode and map adjustments matter. In a one-versus-one the two scenarios above apply directly. In a team or free-for-all game the Doomsday Clock is the dominant source of no-man’s-land, so the clearing race is the central decision and a single player’s scar can deny an entire teammate’s front. On compact maps the Hydrogen scar is a map-level event that can win or lose the game in one shot, while on large maps the same scar is a local denial. On maps with lots of water, a water nuke is often a better tool than a fallout nuke because it creates a permanent water boundary instead of a retake-tax scar. The universal adjustment is to always evaluate the scar against the current denominator and the current front, because the same nuke is a winning move in one position and a wasted gold in another, and the difference is entirely a function of where the scar lands relative to the land you must own to win. One final adjustment is the order of your own moves: because the scar is permanent and the retake tax is highest on the first strike, the correct sequence is to set the scar you want, then hold the clean land behind it, then recompute the denominator once the scar has settled, rather than to react to the scar after you have already committed an army to the scarred tiles.

The repeatable decision table and official sources

The table below consolidates the four terrain sources of no-man’s-land and the three effects each one produces, so you can look up the decision before you spend the gold. Every number is from the v0.34.22 tag. The first column is the source of the scar, the second is the footprint it buys, the third is the retake tax it imposes, and the fourth is what it does to the win denominator.

The single sentence to carry out of this guide is that a nuke is a map-editing tool that simultaneously raises the retake cost of the scarred land, lowers the win threshold by shrinking the non-fallout denominator, and does both of them permanently. The decision framework is therefore three questions in order: first, what is the retake tax on the land I am about to scar, and does that tax serve my plan or punish me? Second, what does the scar do to the win denominator, and does the shrinking pie help me or my opponent? Third, is the scar worth the gold, given that it is permanent and will define the board for the rest of the match? If the answer to all three is yes, fire; if any one is no, hold. The official sources for every number on this page are the OpenFrontIO repository at github.com/openfrontio/OpenFrontIO, the v0.34.22 release tag at github.com/openfrontio/OpenFrontIO/releases/tag/v0.34.22, and the specific files Config.ts for the falloutDefenseModifier and the blast radii, WinCheckExecution.ts for the non-fallout denominator, NukeExecution.ts for the setFallout(true) conversion, and DoomsdayClockExecution.ts for the rot. The related guides to read next are the which nuke to commit guide, the water nukes guide, and the nuclear stalemate breaker guide. If the v0.34.22 tag moves or a future release changes the multiplier or the win threshold, the numbers in this table and the two scenarios above are the ones that must be re-verified before you trust the strategy again.