OpenFront Spawn Kill Defense: Surviving an Adjacent Full-Send

The Direct Answer: Surviving an Adjacent Full-Send

An adjacent full-send is a single event with a fixed cost, and the opening is decided before you spend a single troop on a player. A full-send is the neighbor’s first move being the maximum they can commit: the whole reserve into your first tile, sent the instant the spawn window closes. The window your spawn grants you is short — measured by the server in ticks, 50 ticks for the default public FFA at 100 milliseconds per tick, and longer still in the two-versus-two and team modes — so the real decision is not the window itself but what you do with your border the instant it ends.

Three facts set up the whole opening. First, during the window a human cannot send a full-force player attack at you, because the game rejects human attacks on a player who is still immune; a Hard-AI nation, by contrast, is not subject to that rule and can commit its force the moment it is ready, so a nation on your border is a threat the whole time and the window does not protect you from it. Second, you can still expand into neutral land and capture bots during the window, because that path does not check player immunity — the window blocks player-versus-player full-sends, not your own growth into free space, which means the window is a growth window rather than an attack window. Third, the first tile you meet the opponent on has a terrain cost: Plains is the cheapest ground to hold and to take, Highland is moderately harder, and Mountain is the most expensive for both sides, so the border you meet on decides how much the first push costs the attacker.

The reserve is the asset that pays for every one of those facts. The default attack sends about one-fifth of your current troops, so a full click at a typical early population spends a fixed fraction you can calculate before the window closes. If you have already spent that fraction expanding into neutral land, the instant the window closes you have nothing left to hold the border, and the neighbor’s first push takes your edge with almost no resistance. The players who survive the opening keep a large reserve behind the leading edge specifically so the first border is defended, not exposed, and that is the single habit that separates a held border from a lost one.

So the opening is a sequence, not a reflex. Grow into neutral land while the window holds. Keep a large reserve behind the leading edge so that the moment the window closes you still have enough troops to hold a short border. The instant it closes, read one thing: does the neighbor commit? If they do, you defend a short, cheap border with a big reserve. If they do not, you keep growing and only commit troops where the terrain and your reserve justify it. You win or lose the opening by the first move after the window, not by the click you made during it.

This page owns that first thirty seconds: the immunity window, the adjacent full-send, the terrain and reserve math, and the single first move. It stops before mid-game border play, which the other guides cover.

What Actually Makes a Spawn Kill Happen

A spawn kill is not bad luck; it is a choice the neighbor made, made possible by the specific numbers in front of them. Understanding the mechanics turns a panic event into a readable one, and it is the difference between “I died in the first minute” and “I defended a short border and lived.”

The immunity window is the first variable. The server measures it in ticks, and the default public-FFA value is 50 ticks at 100 milliseconds per tick. In the two-versus-two mode the window is set to 30 seconds, and in team modes to 60 seconds; those longer windows are the ones where an adjacent full-send feels survivable, because you have time to build a reserve and a defense post before the first commitment. The default FFA window is short enough that the decision comes fast, which is exactly why the first move matters so much.

The second variable is who is on your border. A human neighbor is frozen for the window and then chooses to commit or not; a Hard-AI nation is not frozen by the player rule, so it can be sending its force the entire time the window is open. This is the single most important distinction for the opening: if your border touches a nation rather than a human, you cannot rely on the window to protect you, and you should treat the first second as the first attack. The source rule is explicit that only human attackers respect PVP immunity, so a nation’s full-send is live from second zero.

The third variable is the reserve. The default attack sends about one-fifth of your current troops (the default land-attack percentage is one-fifth of your troop count, and the default attack-ratio setting is also one-fifth), which means a single full click at a typical early population spends a fixed fraction you can calculate in advance. If you have already spent that reserve expanding, the moment the window closes you have nothing left to hold a border, and the neighbor’s first push takes your first city or your edge with almost no resistance. The players who survive the opening are the ones who keep a large reserve behind the leading edge specifically so that the first border is defended, not exposed.

The fourth variable is the border shape. A short, straight border against Plains is cheap to defend and cheap to attack; a long, curved border against Highland or Mountain is expensive for both sides, which means it favors the defender. A neighbor who spawns on a Mountain edge next to your Plains is already at a cost disadvantage on the first tile, and a neighbor who spawns on your Plains side is the one who will be sending. Reading the border shape before the window closes is what lets you pick the right first move when it does close.

The Decision Framework: Hold, Probe, or Retreat

Every adjacent full-send forces one of three moves, and picking the wrong one is the most expensive error in the first minute. The framework is not about bravery or caution in the abstract; it is about comparing your reserve, your terrain, and the neighbor’s likely intent, then committing to exactly one move.

Hold is the default. You keep your reserve, hold the short border, and let the neighbor spend troops attacking your cheapest ground while your economy grows behind it. Hold is correct when your reserve is large, your border is short and on favorable terrain, and the neighbor is a human who will commit troops they then cannot fully recover. The hold is not passive: you re-expand into neutral land and recapture a bot or two behind the line so the reserve keeps growing. If the neighbor’s push slows and their troops are committed beyond their own reserve, the hold wins on its own, because you are growing while they are stagnant on your edge.

Probe is the second move. You send a small, recoverable attack into the neighbor’s first tile to learn three things at once: their terrain cost, their reserve size, and whether they are a human who can respond or a nation that will simply absorb the push. Probe is correct when your reserve is moderate and you are uncertain about the neighbor’s strength, or when you are on Highland/Mountain and need to confirm whether a full-send is even profitable for them. The probe uses the default one-fifth fraction and no more, so a failed probe costs you the fraction you can afford to lose and teaches you the number that decides the next move. A probe that reveals the neighbor has no reserve behind the first tile turns into an immediate hold-and-grow, because their push has no follow-up.

Retreat is the last move, and it is only correct when the other two are impossible. You give up the edge, pull the reserve back to a second line, and buy time with terrain. Retreat is correct when your reserve is too small to hold the border, the neighbor is a nation committing a force you cannot match, or the border is on your worst terrain with the neighbor on their best. The retreat is not a surrender of the game; it is a conversion of a losing first border into a second, cheaper border where your reserve can recover. The failure of retreat is not the retreat itself but doing it late, after the reserve is already committed and the second line is gone.

The framework’s single rule is that the move is decided by the reserve, not by the click. If you can hold with your reserve, you hold. If you cannot hold but can afford to learn, you probe. If you cannot afford to learn, you retreat. Every full-send the neighbor sends is a number, and the number that decides the move is the one behind the reserve.

Scenario A: You Spawn on Plains and They Full-Send

This is the most common and most dangerous opening. You spawn on a Plains pocket, the border is short and straight, and a human neighbor spawns on your Plains side and commits the full force the instant the window closes. Your reserve is the default one-fifth fraction from a typical early population, and you have spent the rest expanding into neutral land and a bot or two.

The first move is a hold. You do not click the neighbor’s tile, because a full click spends your entire reserve and leaves the border exposed. Instead you keep the reserve and let their push hit your Plains edge. Plains is the cheapest ground to defend, so their push loses the minimum it can, and your reserve is still large enough to hold. The read is their push speed: if their first wave stalls within two or three seconds, their troops are committed and they have no follow-up, so the hold wins on its own and you re-expand into neutral land behind the line. If their push keeps moving, they have a second reserve, and the hold alone is not enough.

The second move is the probe. You send the default one-fifth fraction into their first tile, not to take it but to learn. If their terrain cost is high (they are on Highland or Mountain behind the Plains), the probe bounces and their push slows, which confirms you can hold and grow. If their terrain cost is low and they absorb the probe, you have confirmed they have a second reserve, and the next move is a controlled retreat to a second line on slightly better terrain. The probe is the move that turns “I think they are strong” into a number you can act on, and it costs exactly the fraction you can afford.

The numbers that decide the scenario: a short Plains border at the default one-fifth reserve holds against a single full-send, because the defender’s terrain cost is the lowest and the attacker’s push has no follow-up once committed. The failure is clicking the full force into the first tile during the window, which does nothing (the human attack on an immune player is rejected) and then, the instant the window closes, you have no reserve left because the click committed your troops to a push that never connected. The lesson is that the window is not a time to attack; it is a time to keep growing and keep the reserve.

Scenario B: A Hard-AI Nation Spawns on Your Highland

This is the opening where the immunity window does not protect you at all. A Hard-AI nation spawns on your Highland side and is not subject to the player-immunity rule, so it can commit its force from second zero. Your reserve is the default one-fifth fraction, your border is on Highland (more expensive than Plains but cheaper than Mountain), and you have just two seconds of neutral growth before the nation’s first push arrives.

The first move is different from Scenario A because there is no window to wait for. You cannot rely on the immunity to hold the border, so the first second is already the first attack. The move is a short, immediate hold combined with a fast probe: you keep the reserve on the Highland edge and send the default one-fifth fraction into the nation’s first tile to learn its terrain cost and reserve. Nations have a predictable reserve based on their starting strength, so the probe tells you whether their push has a follow-up. If the nation’s first wave is strong but their second is not, you hold the Highland and let the push run out, then re-expand into neutral land behind the line.

The second move is a controlled retreat to Mountain if the nation’s push keeps coming. Mountain is the most expensive ground for the nation to take, so retreating from Highland to Mountain is a trade that buys time: their push slows on the Mountain cost, your reserve recovers behind the second line, and you can hold the Mountain edge with a smaller force than the Highland edge. The retreat is not a loss; it is a conversion of a losing Highland border into a defensible Mountain border where the terrain cost works for you.

The numbers that decide the scenario: a Highland border against a Hard-AI nation is not survivable with the default reserve alone, because the nation commits from second zero and has no window to wait out. The move that wins is the fast probe followed by the Mountain retreat, which uses the terrain cost differential to hold a second line. The failure is treating the nation like a human neighbor, waiting for a window that does not exist, and then finding the reserve already committed to a Highland edge the nation is taking. The lesson is that the immunity window protects you from humans, not from Hard-AI nations, and the opening against a nation is decided in the first two seconds.

Failure Modes and the Counter-Moves

The opening fails in four specific ways, and each one has a counter-move that is cheaper than the failure. Knowing the failure modes in advance is what lets you pick the right move when the window closes, because the failure is the move you are about to make, and the counter is the move you should make instead.

Failure 1: Clicking the full force during the window. The instinct is to attack the adjacent neighbor the instant you see them, because they are the only player on your border and the window is about to close. The click does nothing against a human (the attack on an immune player is rejected), and the instant the window closes your troops are committed to a push that never connected, so you have no reserve left to hold the border. The counter is to use the window for neutral growth and bot capture only, keeping the reserve intact. The window is a growth window, not an attack window.

Failure 2: Sending the default one-fifth into a defended first tile. The instinct is to probe by sending the default fraction into the neighbor’s first tile, but if their first tile is defended by a defense post, the defense post’s defense multiplier makes the attack lose more than the fraction you can afford, and the push bounces with your reserve already spent. The counter is to read the defense post before the probe: a defense post over a thirty-tile radius multiplies the defender’s magnitude and the tile cost, so a probe into a defended tile is a guaranteed loss of the fraction. If the first tile is defended, the probe is a retreat, not a commit.

Failure 3: Expanding past the reserve into a full-send. The instinct is to keep expanding into neutral land and bots, spending the reserve on growth, because growth is what wins the midgame. But the moment the window closes and the neighbor full-sends, you have no reserve left to hold the border, and the first push takes your edge with no resistance. The counter is to stop expanding the instant you are adjacent to a human, and keep the reserve behind the leading edge specifically so the first border is defended. Growth after the window is fine; growth during the window that spends the reserve is the failure.

Failure 4: Treating a Hard-AI nation like a human neighbor. The instinct is to wait for the immunity window to close before committing, but the window does not apply to Hard-AI nations, so by the time the window closes the nation’s push is already on your edge and your reserve is committed to a losing border. The counter is to treat the first second as the first attack against a nation: a fast probe and a controlled retreat to Mountain, which uses the terrain cost to hold a second line. The window protects you from humans, not from nations, and the opening against a nation is decided in the first two seconds.

The single rule that covers all four failures is that the reserve is the asset and the click is the cost. Every failure is a click that spends the reserve on a move that does not defend the border, and every counter is a move that keeps the reserve behind the line. The opening is won by the reserve, not by the click.

Mode and Map Adjustments

The same three-move framework changes by mode and by map, and the version-sensitive numbers are the ones that shift most. The mode changes the immunity window, the map changes the terrain cost, and together they decide whether the hold, the probe, or the retreat is the default move.

The source-verified windows are the numbers below. The default public-FFA window is set in ticks (50 ticks at 100 milliseconds per tick), the two-versus-two mode is set to 30 seconds, and the team mode is set to 60 seconds. These are the version-sensitive values, and they are the ones that decide the timing of the first move.

Mode	Immunity window	Default first move	Why
Public FFA	50 ticks (default)	Hold with a fast probe	Short window, reserve still large, intent revealed fast
2v2	30 seconds	Hold with a defense post	Long window, time to build a post on the first tile
Team	60 seconds	Hold with a post network	Longest window, coordinated full-send needs a network

Default public FFA is the short-window mode, where the immunity is measured in ticks and the decision comes fast. The default move is a hold with a fast probe, because the window is short enough that the neighbor’s intent is revealed quickly and the reserve is still large. The map matters here: a Plains-heavy map makes the hold cheap (the defender’s terrain cost is the lowest), and a Mountain-heavy map makes the hold expensive (the defender’s terrain cost is the highest), so a Mountain-heavy map pushes the default toward a probe or a retreat.

Two-versus-two (2v2) is the long-window mode, where the immunity is set to 30 seconds. The long window means you have time to build a reserve and a defense post before the first commitment, so the default move is a hold with a defense post on the first tile. The 30-second window is the opening where a defense post on the first tile is worth its cost, because the hold has time to be defended by the post’s multiplier. The map matters here too: a Plains-heavy 2v2 map makes the hold-and-post the clear win, and a Mountain-heavy 2v2 map makes the hold-and-post the expensive loss.

Team modes are the longest-window modes, where the immunity is set to 60 seconds. The 60-second window means you have time to build a full reserve and a defense post network before the first commitment, so the default move is a hold with a defense post network and a reserve behind it. The team context also means the neighbor is likely a team, so the full-send is coordinated and the hold must be defended by the post network, not a single post. The map matters here: a Plains-heavy team map makes the hold-and-network the clear win, and a Mountain-heavy team map makes the hold-and-network the expensive loss.

Map terrain is the second adjustment. A Plains border is cheap to hold and cheap to attack, so the default is a hold; a Highland border is moderately more expensive, so the default is a hold with a probe; and a Mountain border is the most expensive, so the default is a probe or a retreat. The terrain cost differential is the number that decides the move, and it is the version-sensitive number that shifts most between maps. The single rule is that the map decides the terrain cost, the mode decides the window, and together they decide the default move.

Building and Upgrades for the Opening

The opening is not just a troop decision; it is a building decision, and the two most useful buildings for the first thirty seconds are the defense post and the city. The defense post is the opening-specific building, and the city is the growth-specific building, and the timing of each one is what decides whether the hold, the probe, or the retreat is survivable.

The defense post is the opening-specific building because its range covers thirty tiles and its multipliers apply to the first tile you meet the opponent on. The defense post’s defense multiplier makes the defender’s magnitude much higher over a thirty-tile radius, and its speed multiplier makes the attacker’s tile cost much higher, so a defense post on the first tile turns a losing hold into a winning one. The timing is mode-dependent: in the default FFA the window is too short to build a defense post before the first commitment, so the defense post is only worth building if you have a long enough reserve to afford the build time; in the 2v2 and team modes the window is long enough that the defense post on the first tile is worth the cost, because the hold has time to be defended by the post’s multipliers. The rule is that the defense post is an opening building in the long-window modes and a mid-game building in the short-window mode.

The city is the growth-specific building because it increases your maximum troop capacity, which is the number that decides the reserve. The city’s cost scales with your existing economy, so building a city too early (before you have the gold) leaves the reserve unchanged and the hold exposed, and building a city too late (after the hold is decided) wastes the growth that would have defended the border. The timing is reserve-dependent: if your reserve is large enough to hold the border, the city is a mid-game building that grows the reserve for the next border; if your reserve is too small to hold the border, the city is the opening building that grows the reserve before the first commitment. The rule is that the city is an opening building when the reserve is the constraint and a mid-game building when the reserve is sufficient.

The port and the factory are not opening buildings, and building them in the first thirty seconds is a mistake, because they do not defend the first border and they spend gold that should have gone to the reserve or the defense post. The port is a mid-game building that grows the economy for the next border, and the factory is a mid-game building that grows the troop network for the next border. The rule is that the opening is a troop and a terrain decision, not an economy decision, and the economy buildings are for the border after the first one.

The single rule is that the opening is a defense decision first and a growth decision second, and the buildings you buy in the first thirty seconds should defend the first border, not grow the second one. The defense post defends the first border in the long-window modes, the city grows the reserve when it is the constraint, and the port and the factory are for the border after the first one.

Reading the Neighbor Before the Window Closes

The opening is decided before the window closes, and the read is the single most important move in the first thirty seconds. The read is not a prediction of the neighbor’s intent; it is a calculation of the neighbor’s likely first move based on their terrain, their reserve, and their mode. A correct read turns the hold, the probe, and the retreat from guesses into calculated moves, and an incorrect read is the failure that spends the reserve on the wrong move.

The terrain read is the first read. You look at the terrain the neighbor is on and the terrain you are on, and you calculate the terrain cost differential. If the neighbor is on Mountain and you are on Plains, the neighbor’s push is expensive and the hold is the default. If the neighbor is on Plains and you are on Mountain, the neighbor’s push is cheap and the probe or the retreat is the default. The terrain cost differential is the number that decides the first move, and it is the version-sensitive number that shifts most between maps. The rule is that the terrain read is done in the first two seconds, before the window closes, and it decides the default move.

The reserve read is the second read. You look at the neighbor’s troop count and you calculate their likely reserve based on the default one-fifth fraction. If the neighbor’s troop count is low, their reserve is small and the hold is the default. If the neighbor’s troop count is high, their reserve is large and the probe or the retreat is the default. The reserve read is done in the first two seconds, and it decides whether the hold is survivable. The rule is that the reserve read is a number, not a guess, and the number is the neighbor’s troop count times the default one-fifth fraction.

The mode read is the third read. You look at the mode and you calculate the immunity window. If the mode is the default FFA, the window is short and the read is fast. If the mode is the 2v2 or team mode, the window is long and the read is slow. The mode read decides how much time you have to make the first move, and it is the version-sensitive number that shifts most between modes. The rule is that the mode read is done in the first second, and it decides the timing of the first move.

The nation read is the fourth read, and it is the most important. You look at whether the neighbor is a human or a Hard-AI nation, and you calculate whether the immunity window applies to them. If the neighbor is a human, the window applies and the hold is the default. If the neighbor is a nation, the window does not apply and the first second is the first attack. The nation read is done in the first second, and it decides whether the window protects you at all. The rule is that the nation read is the first read, and it decides whether the other reads matter.

The single rule is that the read is a calculation, not a prediction, and the calculation is the terrain cost differential, the reserve number, the mode window, and the nation status, all done in the first two seconds before the window closes. A correct read turns the three-move framework into a calculated move, and an incorrect read is the failure that spends the reserve on the wrong move.

The 30-Second Checkpoint: What the Opening Should Have Given You

The opening is a process, and the thirty-second checkpoint is the moment you judge whether the process worked. The checkpoint is not a win or a loss; it is a set of four conditions that, if met, mean the opening was a success and the midgame is winnable. If the conditions are not met, the checkpoint tells you which failure mode you are in and which counter-move to make.

Condition 1: The reserve is still behind the line. The reserve is the asset, and if the reserve is still behind the leading edge at the thirty-second mark, the opening was a success. If the reserve is committed to a push that never connected, the opening was a failure, and the counter-move is a controlled retreat to a second line where the reserve can recover. The reserve is the single most important number at the checkpoint, and it is the number that decides whether the midgame is winnable.

Condition 2: The first border is held or traded. The first border is the decision, and if the first border is held (the neighbor’s push ran out) or traded (you gave up the edge for a second, cheaper border), the opening was a success. If the first border is lost (the neighbor took your edge with no resistance), the opening was a failure, and the counter-move is a retreat to a second line where the terrain cost works for you. The first border is the decision that the reserve made, and it is the number that decides whether the midgame is a recovery or a win.

Condition 3: The economy is intact. The economy is the growth engine, and if the economy is intact at the thirty-second mark (no city lost, no port lost, the gold is still available), the opening was a success. If the economy is damaged (a city lost, the gold spent on a losing push), the opening was a failure, and the counter-move is a focus on the reserve and the terrain, not the economy, for the next thirty seconds. The economy is the growth engine for the midgame, and it is the number that decides whether the midgame is a recovery or a win.

Condition 4: The next move is known. The next move is the read, and if the next move is known at the thirty-second mark (you know whether the neighbor will commit, probe, or retreat, and you know the move to make in response), the opening was a success. If the next move is unknown (you do not know the neighbor’s intent, and you do not know the move to make in response), the opening was a failure, and the counter-move is a probe that reveals the neighbor’s reserve and terrain cost. The next move is the read that the reserve made, and it is the number that decides whether the midgame is a calculated move or a guess.

The single rule is that the thirty-second checkpoint is a process check, not a result check. Winning the opening is not the goal; surviving the opening with the reserve behind the line, the first border held or traded, the economy intact, and the next move known is the goal. If the four conditions are met, the midgame is winnable, and the next guide covers the midgame border play. If the conditions are not met, the checkpoint tells you the failure mode and the counter-move, and the next thirty seconds are a recovery, not a win.

The opening is the most important thirty seconds in the game, because it is the only thirty seconds where the decision is the reserve and the move is the hold, the probe, or the retreat. The rest of the game is a continuation of the decision the opening made, and a strong opening preserves the choices for the midgame. For the midgame border play that follows the first thirty seconds, read the land combat guide, which covers the border reads once the opening is decided. For the growth timing that the reserve depends on, read the tall versus wide guide, which decides when to convert the reserve into buildings. For the terrain decision that the first border is made on, read the map strategy guide, which covers the Plains, Highland, and Mountain tradeoffs in depth. For the reserve math that the default one-fifth fraction comes from, read the attack ratio guide, which covers the percentage setting and the push-speed rule. For the first-match loop that this guide specializes, read the first-match guide, which covers the spawn choice and the safe expansion. This guide covers the first thirty seconds, and the first thirty seconds are where the game is won or lost.