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Difference between revisions of "Exploit"
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An '''exploit''' is a quirk of a game that allows players to gain what other players may consider an unfair advantage, usually by making use of a feature that is not working properly or which defies logic. 'Exploiting the game' is distinct from '[[cheating]]' because exploits occur within the game as written and do not need any external [[utilities]] or [[modding]]. Whether a player chooses to make use of an exploit or not depends on their personal taste; given that ''[[Dwarf Fortress]]'' is a single-player game, the user alone can decide what liberties to take and what options to shun. Among DF players, there is much discussion about what actually should be considered an exploit, ranging from making [[dwarven syrup]] instead of [[dwarven sugar]], growing crops in winter, or even underground, at the one extreme, to justifying 'water wheel batteries' at the other. This page takes a rather relaxed approach in that you considering it an exploit is basically enough to add it, if you don't get too much opposition. | An '''exploit''' is a quirk of a game that allows players to gain what other players may consider an unfair advantage, usually by making use of a feature that is not working properly or which defies logic. 'Exploiting the game' is distinct from '[[cheating]]' because exploits occur within the game as written and do not need any external [[utilities]] or [[modding]]. Whether a player chooses to make use of an exploit or not depends on their personal taste; given that ''[[Dwarf Fortress]]'' is a single-player game, the user alone can decide what liberties to take and what options to shun. Among DF players, there is much discussion about what actually should be considered an exploit, ranging from making [[dwarven syrup]] instead of [[dwarven sugar]], growing crops in winter, or even underground, at the one extreme, to justifying 'water wheel batteries' at the other. This page takes a rather relaxed approach in that you considering it an exploit is basically enough to add it, if you don't get too much opposition. | ||
− | = Fortress | + | = Fortress mode exploits = |
== Atom smasher == | == Atom smasher == | ||
{{main|Dwarven atom smasher}} | {{main|Dwarven atom smasher}} | ||
− | Lowering a raised [[drawbridge]] can be used to obliterate most creatures or items beneath it. | + | Lowering a raised [[drawbridge]] can be used to obliterate most creatures or items beneath it, with some exceptions: |
+ | |||
+ | * Atom smashing a creature with a size over 1200000 will destroy the drawbridge. | ||
+ | * [[Contaminant]]s are unaffected. | ||
+ | * Smashing a bag of something will destroy the bag, but spill its contents. | ||
+ | * [[Artifact]]s have a special exception; whereby upon being atom-smashed, they will be "hidden" and inaccessible for the rest of the playthrough. See the main article for further details. | ||
==Manager exercise program== | ==Manager exercise program== | ||
− | As a [[manager]], skill is gained as tasks are approved, not completed. Simply by queuing lots of jobs ({{ | + | As a [[manager]], skill is gained as tasks are ''approved'', not completed. Simply by queuing lots of jobs ({{menu icon|o}} - [[File:New work order icon.png|30px]]) and providing a meager office, the manager will quickly level to [[legendary]] as an [[Organizer]]. The tasks can then be removed once approved. |
==Merchant swindles== | ==Merchant swindles== | ||
Line 20: | Line 27: | ||
* Tearing down the [[trade depot]] while the merchants are there is the easiest way to seize all merchant goods at once. | * Tearing down the [[trade depot]] while the merchants are there is the easiest way to seize all merchant goods at once. | ||
− | * Marking items for [[dump]]ing | + | * Marking items for [[dump]]ing by cliсking on [[File:Dump option icon.png|30px]] on item or in stocks menu ({{key|k}}), or mass dump mode ({{key|i}}-{{key|p}}) then marking the entire depot, lets you relieve merchants of their goods. Just reclaim the items from your garbage dump [[zone]] later. You can even take clothing and equipment off merchant and guards this way. |
* You can make a wall around the merchants (and even the poor animals) and let them starve to death, letting you take whatever you want. Wait quite a while for them to starve. They will become [[Insanity|very angry]] if you do, so never open the door once they are on the brink of death. | * You can make a wall around the merchants (and even the poor animals) and let them starve to death, letting you take whatever you want. Wait quite a while for them to starve. They will become [[Insanity|very angry]] if you do, so never open the door once they are on the brink of death. | ||
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== Quantum stockpiles == | == Quantum stockpiles == | ||
{{main|Quantum stockpile}} | {{main|Quantum stockpile}} | ||
− | A quantum stockpile (QSP) allows you to store an infinite number of items in a single tile. QSPs can make for super efficient storage, allowing more compact fortresses, shorter hauling routes, more efficient manufacturing flows, stocktaking at a glance | + | A quantum stockpile (QSP) allows you to store an infinite number of items in a single tile. QSPs can make for super efficient storage, allowing more compact fortresses, shorter hauling routes, more efficient manufacturing flows, and stocktaking at a glance by simply clicking on it. |
== Building destroyer door == | == Building destroyer door == | ||
Line 48: | Line 55: | ||
The same thing goes for things stored in [[bag]]s. Each unit of [[sand]] comes in its own bag, and since each unit of sand costs only 1 embark point while bags cost a minimum of 10 embark points each, you can get bags for ten times cheaper by buying sand, then [[dumping]] out the sand after embark. | The same thing goes for things stored in [[bag]]s. Each unit of [[sand]] comes in its own bag, and since each unit of sand costs only 1 embark point while bags cost a minimum of 10 embark points each, you can get bags for ten times cheaper by buying sand, then [[dumping]] out the sand after embark. | ||
+ | |||
+ | One down side is that all those containers then need to be individually hauled from the wagon to where ever you want them. | ||
== Infinite metal == | == Infinite metal == | ||
− | Because one bar of metal produces 25 bolts, and a single bolt can be melted to 0.1 bars of metal, you can create unlimited adamantine wafers in your fortress using a [[Stupid_dwarf_trick# | + | Because one bar of metal produces 25 bolts, and a single bolt can be melted to 0.1 bars of metal, you can create unlimited [[adamantine]] wafers in your fortress using a [[Stupid_dwarf_trick#Bolt splitting operation|clever setup]] with marksdwarves to separate the stacks of [[adamantine]] bolts into single bolts. See this [http://www.bay12forums.com/smf/index.php?topic=51423.0 forum thread] for more details. |
Weapon traps filled with crossbows will be loaded with individual bolts (10 per crossbow). Bolts cannot be designated to melt while loaded in the trap. It requires deconstruction of the trap. The components will scatter on deconstruction so surrounding the trap with an ammo stockpile set to links only and using dfhack automelt can semi-automate the process. Any metal components of the trap may also be melted. | Weapon traps filled with crossbows will be loaded with individual bolts (10 per crossbow). Bolts cannot be designated to melt while loaded in the trap. It requires deconstruction of the trap. The components will scatter on deconstruction so surrounding the trap with an ammo stockpile set to links only and using dfhack automelt can semi-automate the process. Any metal components of the trap may also be melted. | ||
− | Coins may also be split at a [[trade depot]] and melted down individually for up to a 50x return. | + | Coins may also be split at a [[trade depot]] and melted down individually for up to a 50x return. Mint a stack of coins, then trade it to a caravan. You can then buy the stack back in pieces, and each individual smaller stack will melt and produce .1 bars. One bar produces 500 coins, but splitting it into stacks of 1 coin each would create 500 melt jobs, producing 50 bars in return. The process is discussed in greater detail, both with and without use of macros on this [http://www.bay12forums.com/smf/index.php?topic=111680.0 forum thread]. While potentially time-consuming, this new method both results in far more bars produced per stack (potentially a net profit of 49 bars instead of 1.5), and can duplicate any metal, not just military ones while simultaneously training your broker. Combined with a magma smelter and properly written macros, this method turns a smelter into a free metal generator. Those who are less patient may instead opt to simply melt the coin stacks immediately after they are minted - while this yields only a 10% gain, it is far less time-consuming. As of v50, this no longer works as coin stacks have to be bought back from the trader in full, as there is no option to buy back individual coins. However, melting a full stack of 500 coins will still produce 1.1 bars and can still be used to duplicate metal (including [[adamantine]]) as of v50. |
+ | |||
+ | Recent dwarven !!SCIENCE!! has shown that certain visitors react badly to being trapped in a vault of treasure and can be used to [https://www.reddit.com/r/dwarffortress/comments/fql316/infinite_adamantine_using_elf_labor/ rapidly split stacks of coins]. Be careful what you wish for. | ||
− | For multiplying weapons/armor-grade metals, forging and melting giant axe blades, | + | For multiplying weapons/armor-grade metals, forging and melting giant axe blades, enormous corkscrews, menacing spikes, and leggings will yield a 50% gain per item; note that this does ''not'' work with [[adamantine]], since adamantine goods require 3 times as many wafers, instead leading to a 70% loss per item. |
See the [[Melt item]] article for the best yields when melting down items made of mundane metals for the current version. | See the [[Melt item]] article for the best yields when melting down items made of mundane metals for the current version. | ||
== Quick trade goods == | == Quick trade goods == | ||
− | + | [[Bolt|Bolts]], having a high stack size and being affected by quality modifiers, make excellent trade goods when made by a highly trained woodcrafter or metalsmith. This is because quality adds a flat amount to ''each bolt'''s value, going as high as 375☼ on exceptional, and 750☼ on masterwork bolts, making even cheap wooden bolts a quick way of buying out caravans. | |
− | |||
− | |||
− | + | [[Prepared meal]]s can be quick and valuable trade goods - purchase an abundance of raw food when the traders arrive, and set your [[kitchen]] to work cooking that food into lavish meals, then haul the stacks of meals back to the depot and trade them for whatever supplies you really want. The caravan will buy back meals composed of their own ingredients at 25x to 100x their initial value. | |
− | [[ | + | Single task [[instruments]] can also be a very lucrative business, although glass instruments have lower gains. |
== Silk farm == | == Silk farm == | ||
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== Danger room == | == Danger room == | ||
{{Main|Danger room}} | {{Main|Danger room}} | ||
− | An [[Trap#Upright Spear/Spike|upright spike trap]] full of non-masterwork training spears (''not'' menacing spikes or metal spears, or even [[elf|elven]] wooden spears) is linked to a [[lever]], which is pulled repeatedly | + | An [[Trap#Upright Spear/Spike|upright spike trap]] full of non-masterwork training spears (''not'' menacing spikes or metal spears, or even [[elf|elven]] wooden spears) is linked to a [[lever]], which is pulled repeatedly, and dwarves are stationed on the trap. The dwarves quickly learn how to dodge, block and parry these "attacks", gaining [[combat skill]]s much more quickly than through normal [[training]], unless they die. |
+ | |||
+ | This exploit does not work in newer versions due to changes to damage propagation.{{version|0.43.04}} | ||
== Coinstar room == | == Coinstar room == | ||
{{Main|Danger room#Coinstar room|l1=Danger room § Coinstar room}} | {{Main|Danger room#Coinstar room|l1=Danger room § Coinstar room}} | ||
A coinstar or popcorn room trains [[armor user]] skills via repeated (unblockable/undodgeable) impacts of various small objects such as [[coin]]s, [[seed]]s, [[sock]]s, [[leaves]], or other small, light objects. Channel a 1x2 trench (leaving ramps), and build two 1x1 '''retracting''' bridges on the bottom of the trench. Connect the bridges to a lever. Add coins (stacks of 15 or smaller are 100% safe) and dwarves. | A coinstar or popcorn room trains [[armor user]] skills via repeated (unblockable/undodgeable) impacts of various small objects such as [[coin]]s, [[seed]]s, [[sock]]s, [[leaves]], or other small, light objects. Channel a 1x2 trench (leaving ramps), and build two 1x1 '''retracting''' bridges on the bottom of the trench. Connect the bridges to a lever. Add coins (stacks of 15 or smaller are 100% safe) and dwarves. | ||
+ | |||
+ | This exploit does not work in newer versions due to changes to damage propagation.{{version|0.43.04}} | ||
== Wildlife control == | == Wildlife control == | ||
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== Dwarven rocket elevator == | == Dwarven rocket elevator == | ||
− | By exploiting quirks in dwarven physics, minecarts can be accelerated without an external power source (beyond an initial push) to travel independently, or to ascend dozens of Z levels upwards very quickly. Details at [[ | + | By exploiting quirks in dwarven physics, minecarts can be accelerated without an external power source (beyond an initial push) to travel independently, or to ascend dozens of Z levels upwards very quickly. Details at [[Minecart#Impulse_ramps]]. |
+ | |||
+ | == Infinite layer stone without magma == | ||
+ | Constructed walls can be designated for both fortification carving and deconstruction. When the latter designation is completed, the former is kept. When the former is completed after that, stone floor becomes a natural stone fortification. This makes a cycle for infinite stone: | ||
− | = Adventure | + | Stone floor → Build Constructed Wall → Designate for removal and fortification carving → Deconstruct → Stone Floor (still designated as fortification) → Stone fortification → Dug out, stone floor + free stone boulder. (Disable engraving on all dwarves to delay the fortification carving.) |
+ | |||
+ | The material used to construct the wall is reclaimed when it is deconstructed. Since mining doesn't always drop stone there is only a chance of getting stone from the fortification. | ||
+ | |||
+ | Using this, one can also retrieve stone from surface boulders, though as deconstruction leaves behind layer stone it will not duplicate adamantine or anything else. Soil gets carved, but remains as a floor, thus providing no gain. | ||
+ | |||
+ | ([http://www.bay12forums.com/smf/index.php?topic=145317.msg8091746#msg8091746 Original forum post]) | ||
+ | |||
+ | == Alternate water purification methods == | ||
+ | |||
+ | Contamination in the form of salty or stagnant water is apparently unable to climb stairs. Lacking the materials to build a screw pump, you can instead purify water by forcing it to pass through a vertical u-bend made of stairs. | ||
+ | |||
+ | Flowing fresh water destroys stagnant water on contact, converting it into fresh water. Oddly enough, flowing salt water also destroys stagnant water on contact, converting it to fresh water, so connecting your murky pools to the sea paradoxically provides clean drinking water. | ||
+ | |||
+ | = Adventure mode exploits = | ||
== Urist McAdventurer the shield-wall == | == Urist McAdventurer the shield-wall == | ||
Adventurers are not limited in the number of items they can hold in their hands, allowing them to equip a virtually unlimited number of shields or bucklers with little effect to the adventurer's performance. This offers multiple chances to block attacks (vastly reducing the number that cause damage) and quickly trains up the shield user skill, further increasing the effectiveness of those shields. There is an indirect limit on how many shields you can equip based on how the total weight of your adventurer's items affects your speed, but the tradeoff between wearing a dozen (or more) shields is well worth the minor reduction in speed. | Adventurers are not limited in the number of items they can hold in their hands, allowing them to equip a virtually unlimited number of shields or bucklers with little effect to the adventurer's performance. This offers multiple chances to block attacks (vastly reducing the number that cause damage) and quickly trains up the shield user skill, further increasing the effectiveness of those shields. There is an indirect limit on how many shields you can equip based on how the total weight of your adventurer's items affects your speed, but the tradeoff between wearing a dozen (or more) shields is well worth the minor reduction in speed. | ||
− | + | This exploit was made more complicated due to the addition of the ability to holster/draw weapons and shields, which is needed for [[climber|climbing]] and to avoid hostility from local guards. While an infinite number of weapons or shields can be strapped to your body, only the first two such items will be drawn, requiring a free hand for each. Retrieving multiple shields after unequipping them requires manually drawing each individual shield. | |
− | == Infinite drink | + | == Infinite drink == |
− | + | One's thirst can be quenched indefinitely by emptying a waterskin when you only have 1 unit of liquid left, and refilling it from the pool that forms; giving you 3 units of drink. This is especially useful if you managed to find alcohol and fill the waterskin with some, as alcohol never freezes in cold weather. One can also make a potable pool of water, by emptying a waterskin containing saltwater. | |
== Backpack of holding == | == Backpack of holding == | ||
− | In adventurer mode, if you try to pick something up while both your hands are already holding something, it'll go straight in your backpack, even if it would not have fit had you first picked it up and then tried to put it inside. That means you can stuff as much as you want into your backpack | + | In adventurer mode, if you try to pick something up while both your hands are already holding something, it'll go straight in your backpack, even if it would not have fit had you first picked it up and then tried to put it inside. That means you can stuff as much as you want into your backpack - it will still affect your weight and speed, however. |
+ | |||
+ | == Pack adventurer == | ||
+ | You could hold items of any weight, but they affect your speed - except when you're riding a mount. | ||
+ | * [[Jumping]] distance can't become lower than 2-square [[jump]]. Therefore, even overburdened adventurer can quickly move by [[jumping]]. On top of that, [[Jumping]] can be used to jump over various hazards, and to jump on enemies - what damages them, sends them flying and stuns them. | ||
{{Category|Game}} | {{Category|Game}} | ||
[[ru:Exploit]] | [[ru:Exploit]] |
Revision as of 07:51, 6 July 2024
This article was migrated from DF2014:Exploit and may be inaccurate for the current version of DF (v50.15). See this page for more information. |
v50.15 · v0.47.05 This article is about the current version of DF.Note that some content may still need to be updated. |
This article contains massive spoilers. If you do not wish to have your game experience spoiled, do not scroll down! |
An exploit is a quirk of a game that allows players to gain what other players may consider an unfair advantage, usually by making use of a feature that is not working properly or which defies logic. 'Exploiting the game' is distinct from 'cheating' because exploits occur within the game as written and do not need any external utilities or modding. Whether a player chooses to make use of an exploit or not depends on their personal taste; given that Dwarf Fortress is a single-player game, the user alone can decide what liberties to take and what options to shun. Among DF players, there is much discussion about what actually should be considered an exploit, ranging from making dwarven syrup instead of dwarven sugar, growing crops in winter, or even underground, at the one extreme, to justifying 'water wheel batteries' at the other. This page takes a rather relaxed approach in that you considering it an exploit is basically enough to add it, if you don't get too much opposition.
Fortress mode exploits
Atom smasher
Lowering a raised drawbridge can be used to obliterate most creatures or items beneath it, with some exceptions:
- Atom smashing a creature with a size over 1200000 will destroy the drawbridge.
- Contaminants are unaffected.
- Smashing a bag of something will destroy the bag, but spill its contents.
- Artifacts have a special exception; whereby upon being atom-smashed, they will be "hidden" and inaccessible for the rest of the playthrough. See the main article for further details.
Manager exercise program
As a manager, skill is gained as tasks are approved, not completed. Simply by queuing lots of jobs (o - ) and providing a meager office, the manager will quickly level to legendary as an Organizer. The tasks can then be removed once approved.
Merchant swindles
There are a variety of ways to steal cargo from merchants. All amount to naked theft, and the civilization responsible for the caravan will recognize this. Merchants will consider any lost goods to be stolen goods regardless of the method used to take possession of or destroy them (Verification: See the 40d page and This forum post). So unless you specifically want to take the clothing off the backs of the merchants or steal from your own civ, you might as well just seize the goods anyway.
- Seizing goods via the trade dialog is most straightforward way to select specific items to steal; but there are more entertaining methods detailed below.
- Tearing down the trade depot while the merchants are there is the easiest way to seize all merchant goods at once.
- Marking items for dumping by cliсking on on item or in stocks menu (k), or mass dump mode (i-p) then marking the entire depot, lets you relieve merchants of their goods. Just reclaim the items from your garbage dump zone later. You can even take clothing and equipment off merchant and guards this way.
- You can make a wall around the merchants (and even the poor animals) and let them starve to death, letting you take whatever you want. Wait quite a while for them to starve. They will become very angry if you do, so never open the door once they are on the brink of death.
Quantum stockpiles
A quantum stockpile (QSP) allows you to store an infinite number of items in a single tile. QSPs can make for super efficient storage, allowing more compact fortresses, shorter hauling routes, more efficient manufacturing flows, and stocktaking at a glance by simply clicking on it.
Building destroyer door
Forbid something a dwarf is carrying as he goes through a door, and he'll drop it. The door won't close and won't stop any normal creature from going through, but building destroyers seem to stop in their tracks, waiting for it to close before moving on. Note: your civilians can pass the creature safely, but attacking it cancels your protection.[Verify]
HFS's back door
There's a convoluted way to dig down through semi-molten rock and evade the head-on encounter with hidden fun stuff. Doing this can enable you to, among other things, mine undiggable slade and duplicate rare minerals. See the page semi-molten rock for details.
Forgotten beast zoo
Wall off all the passageways into your lowest level at the outermost square of the map - except one, which leads to a little vestibule surrounded by fortifications. Wave hello to the various ungainly "forgotten beasts" which accumulate inside.
Alternatively, by using a giant cave spider or web-spewing forgotten beast to place webs on cage traps you can capture and display non-web-spewing forgotten beasts, titans, and more.
Dwarven water reactor
A screw pump requires 10 power to move water; a water wheel supplies 100 power if it's got water moving it. Arrange the former to feed the latter, while the latter powers the former, and you can get perpetual motion going - with a surplus of power available.
And we'll throw in the barrel or bag for free
On embark, buying things which are stored in barrels gets the barrel for free, with at most 10 items per barrel, so, for example, the 15 units of randomly chosen meat which come with the default supplies will get you two free barrels, one completely filled with 10 units of meat and one half filled with 5 units of meat; you get another two free barrels from the 15 units of randomly chosen fish. You can get rid of all of that food, then for the same cost select one unit each of meat from 30 different kinds of animals, giving you 30 free barrels instead of only 4, since each different kind of animal meat is put in its own barrel. Note that different types of meat from the same kind of animal goes into a single barrel, so choosing 1 yak brain + 1 yak eye + 1 yak spleen will get you only one free barrel instead of three.
The same thing goes for things stored in bags. Each unit of sand comes in its own bag, and since each unit of sand costs only 1 embark point while bags cost a minimum of 10 embark points each, you can get bags for ten times cheaper by buying sand, then dumping out the sand after embark.
One down side is that all those containers then need to be individually hauled from the wagon to where ever you want them.
Infinite metal
Because one bar of metal produces 25 bolts, and a single bolt can be melted to 0.1 bars of metal, you can create unlimited adamantine wafers in your fortress using a clever setup with marksdwarves to separate the stacks of adamantine bolts into single bolts. See this forum thread for more details.
Weapon traps filled with crossbows will be loaded with individual bolts (10 per crossbow). Bolts cannot be designated to melt while loaded in the trap. It requires deconstruction of the trap. The components will scatter on deconstruction so surrounding the trap with an ammo stockpile set to links only and using dfhack automelt can semi-automate the process. Any metal components of the trap may also be melted.
Coins may also be split at a trade depot and melted down individually for up to a 50x return. Mint a stack of coins, then trade it to a caravan. You can then buy the stack back in pieces, and each individual smaller stack will melt and produce .1 bars. One bar produces 500 coins, but splitting it into stacks of 1 coin each would create 500 melt jobs, producing 50 bars in return. The process is discussed in greater detail, both with and without use of macros on this forum thread. While potentially time-consuming, this new method both results in far more bars produced per stack (potentially a net profit of 49 bars instead of 1.5), and can duplicate any metal, not just military ones while simultaneously training your broker. Combined with a magma smelter and properly written macros, this method turns a smelter into a free metal generator. Those who are less patient may instead opt to simply melt the coin stacks immediately after they are minted - while this yields only a 10% gain, it is far less time-consuming. As of v50, this no longer works as coin stacks have to be bought back from the trader in full, as there is no option to buy back individual coins. However, melting a full stack of 500 coins will still produce 1.1 bars and can still be used to duplicate metal (including adamantine) as of v50.
Recent dwarven !!SCIENCE!! has shown that certain visitors react badly to being trapped in a vault of treasure and can be used to rapidly split stacks of coins. Be careful what you wish for.
For multiplying weapons/armor-grade metals, forging and melting giant axe blades, enormous corkscrews, menacing spikes, and leggings will yield a 50% gain per item; note that this does not work with adamantine, since adamantine goods require 3 times as many wafers, instead leading to a 70% loss per item.
See the Melt item article for the best yields when melting down items made of mundane metals for the current version.
Quick trade goods
Bolts, having a high stack size and being affected by quality modifiers, make excellent trade goods when made by a highly trained woodcrafter or metalsmith. This is because quality adds a flat amount to each bolt's value, going as high as 375☼ on exceptional, and 750☼ on masterwork bolts, making even cheap wooden bolts a quick way of buying out caravans.
Prepared meals can be quick and valuable trade goods - purchase an abundance of raw food when the traders arrive, and set your kitchen to work cooking that food into lavish meals, then haul the stacks of meals back to the depot and trade them for whatever supplies you really want. The caravan will buy back meals composed of their own ingredients at 25x to 100x their initial value.
Single task instruments can also be a very lucrative business, although glass instruments have lower gains.
Silk farm
A silk farm can serve as a safe and endless source of silk thread from giant cave spiders or other web-spewing beasts. Its essence is a room with a "bait" creature separated from a web-spewing creature by fortifications. The webber will attempt to attack the "bait" by shooting webs through the fortifications. Weavers can collect the webs as silk thread and create silk cloth.
Dwarven road-dar
Dwarven radar is a handy way of checking for caverns and other special features using the farm plots, paved roads, and activity zones. Know where the caverns are before you designate your carefully planned, fully symmetric living quarters!
For more details, see the forum thread.
Danger room
An upright spike trap full of non-masterwork training spears (not menacing spikes or metal spears, or even elven wooden spears) is linked to a lever, which is pulled repeatedly, and dwarves are stationed on the trap. The dwarves quickly learn how to dodge, block and parry these "attacks", gaining combat skills much more quickly than through normal training, unless they die.
This exploit does not work in newer versions due to changes to damage propagation.v0.43.04
Coinstar room
A coinstar or popcorn room trains armor user skills via repeated (unblockable/undodgeable) impacts of various small objects such as coins, seeds, socks, leaves, or other small, light objects. Channel a 1x2 trench (leaving ramps), and build two 1x1 retracting bridges on the bottom of the trench. Connect the bridges to a lever. Add coins (stacks of 15 or smaller are 100% safe) and dwarves.
This exploit does not work in newer versions due to changes to damage propagation.v0.43.04
Wildlife control
Wild animals will not spawn when a certain number of them are still present on the map (2 for default 4x4 embark, for larger sites it's higher). This works also for cavern creatures (each cavern independently), or even for roaming HFS denizens, and can be exploited to prevent new creatures from a particular layer from spawning. Capture enough wild creatures in cage traps, and release them somewhere they couldn't escape from. As long as they're there, no more beasts will show up. Note that thieving and mischievous creatures are an exception to this, as their arrival is timed and unaffected by the number of other wildlife.
Portable drain
Due to buggy minecart interactions, a minecart on a track stop set to dump into a wall tile will constantly fill and empty, removing large amounts of liquid from the game. This is generally much more convenient than digging a tunnel and carving a fortification at the edge of the map. The effect can be controlled by linking a lever to the track stop (or by adding/removing the minecart in some manner). The portable drain will only reduce the fluid in its tile to below the minimum necessary to fill the cart (6/7); the remaining fluid will need to be dealt with in some other fashion.
Dwarven rocket elevator
By exploiting quirks in dwarven physics, minecarts can be accelerated without an external power source (beyond an initial push) to travel independently, or to ascend dozens of Z levels upwards very quickly. Details at Minecart#Impulse_ramps.
Infinite layer stone without magma
Constructed walls can be designated for both fortification carving and deconstruction. When the latter designation is completed, the former is kept. When the former is completed after that, stone floor becomes a natural stone fortification. This makes a cycle for infinite stone:
Stone floor → Build Constructed Wall → Designate for removal and fortification carving → Deconstruct → Stone Floor (still designated as fortification) → Stone fortification → Dug out, stone floor + free stone boulder. (Disable engraving on all dwarves to delay the fortification carving.)
The material used to construct the wall is reclaimed when it is deconstructed. Since mining doesn't always drop stone there is only a chance of getting stone from the fortification.
Using this, one can also retrieve stone from surface boulders, though as deconstruction leaves behind layer stone it will not duplicate adamantine or anything else. Soil gets carved, but remains as a floor, thus providing no gain.
Alternate water purification methods
Contamination in the form of salty or stagnant water is apparently unable to climb stairs. Lacking the materials to build a screw pump, you can instead purify water by forcing it to pass through a vertical u-bend made of stairs.
Flowing fresh water destroys stagnant water on contact, converting it into fresh water. Oddly enough, flowing salt water also destroys stagnant water on contact, converting it to fresh water, so connecting your murky pools to the sea paradoxically provides clean drinking water.
Adventure mode exploits
Urist McAdventurer the shield-wall
Adventurers are not limited in the number of items they can hold in their hands, allowing them to equip a virtually unlimited number of shields or bucklers with little effect to the adventurer's performance. This offers multiple chances to block attacks (vastly reducing the number that cause damage) and quickly trains up the shield user skill, further increasing the effectiveness of those shields. There is an indirect limit on how many shields you can equip based on how the total weight of your adventurer's items affects your speed, but the tradeoff between wearing a dozen (or more) shields is well worth the minor reduction in speed.
This exploit was made more complicated due to the addition of the ability to holster/draw weapons and shields, which is needed for climbing and to avoid hostility from local guards. While an infinite number of weapons or shields can be strapped to your body, only the first two such items will be drawn, requiring a free hand for each. Retrieving multiple shields after unequipping them requires manually drawing each individual shield.
Infinite drink
One's thirst can be quenched indefinitely by emptying a waterskin when you only have 1 unit of liquid left, and refilling it from the pool that forms; giving you 3 units of drink. This is especially useful if you managed to find alcohol and fill the waterskin with some, as alcohol never freezes in cold weather. One can also make a potable pool of water, by emptying a waterskin containing saltwater.
Backpack of holding
In adventurer mode, if you try to pick something up while both your hands are already holding something, it'll go straight in your backpack, even if it would not have fit had you first picked it up and then tried to put it inside. That means you can stuff as much as you want into your backpack - it will still affect your weight and speed, however.
Pack adventurer
You could hold items of any weight, but they affect your speed - except when you're riding a mount.