Rate-Limited Perpetual Resource

In environmental conservation, perpetual resources are defined as resources that are impossible to run out of, at least on a human timescale. In fictional worlds, it can also be applied to fictional resources, and in the simplified worlds of Video Games, a simplification could be rendering non-perpetual resources as perpetual ones.

And in those latter two cases, this becomes a trope. Bending the rules of reality for an artistic endeavour, a.k.a. Artistic License. Beyond just being perpetual however, all implementations of this trope limit the functional generation rate of these perpetual resources in some manner.

Whether an infinite power source can only have so many hookups, or an infinite mine's extraction depends on the speed and carrying capacity of its miners. If there's no limits, then you have practical infinities instead of technical infinities, and with them, The Omnipotent, since resources are power and omnipotent entities have infinite power.

This is often seen in strategy games and is usually the most annoying part of a Resource-Gathering Mission.

Compare Infinite Supplies, Gradual Regeneration and Easy Logistics. See also Command & Conquer Economy. Money for Nothing is a possible result of this, if resources can be converted to, or is, currency.

Subtrope of Acceptable Breaks from Reality.

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Examples:

Video Games

• Age of Empires III has the Whales, which can be mined for coin. The whales, unlike fish colonies, can be fished up until either the ships are destroyed, the player moves them, or the match ends. The downside is that, unlike the colonies, each whale can only be mined by a max of four fishing ships (including Galleys).
• In Assassin's Creed II, your villa receives income every real-time 20 minutes, and it takes 80 to fill up the war chest. If you don't return to the villa and transfer the coin to your pockets (which are uncapped, for no in-story reason) within the next 20 minutes cycle, any additional income will be forfeit.
• The Battle Cats: Gamatoto can be sent out to different areas for a certain amount of time, to later come back with XP, Cat Food, and other valuable items after a few hours. These areas have an unlimited amount of resources for the taking, but Gamatoto can only bring back so many each time — for example, there's a maximum of 1 of each type of Catseye the expedition team can bring back from Cats Eye Caverns, 2 if Inari is coming along for the expedition as well.
• City-Building Series:
  • All natural resources such as timber or wild game slowly replenish over time even if they're all harvested at the same time, while mines never run out of ore/stone. The only exception is lumber: if a tree is cut down to make room for a road or building, it will never grow back.
  • Trade goods are similarly available only in limited amounts every year, or buyers will only buy up to a maximum. Particularly annoying when you're making more money than you know what to do with, but still can't get building materials for monuments fast enough.
  • Emperor: Rise of the Middle Kingdom: Lumber can be harvested from trees or bamboo. Bamboo produces less lumber per worker, but grows back faster.
  • Pharaoh:
    • Mines never run out of minerals, but they can only be placed near the corresponding type of tile (ore bearing rock for gold and copper, rock for all others). This limits the number of mines that can be placed, not to mention creating pathing nightmares to ensure all the mines are visited by an architect to prevent collapse.
    • Building a Temple Complex to Osiris causes reeds and timber to grow back faster (although it still won't restore trees that were cut down), while pleasing Ra lets you increase trade limits (displease him and they will restrict both exports and imports).
    • Building a Mansion lets the player character pay himself a salary from city funds which goes into a separate treasury used for bribes or emergency cash. Bribes are based on a percentage of your current savings, and the salaries are fixed (up to 100 debens per month) no matter how many thousands of debens the city is raking in from taxes, exports and mines, and transferring money from the city coffers to yours (a popular tactic in earlier games) is expressly forbidden. Paying yourself a lower salary than your rank allows you to draw has the short-term benefit of increasing your Kingdom rating.
  • Zeus: Master of Olympus:
    • Once placed, livestock are essentially infinite but slow sources of food and goods (goats produce cheese while only young cattle are slaughtered, sheep only produce fleece). However, priests from temples will regularly sacrifice livestock, so it's up to the player to watch over their herds and make sure they still have enough animals to keep the city's needs satisfied.
    • Many sanctuaries provide a natural resource, giving the city a locally-produced source if they're otherwise unavailable except by import (but in much smaller quantities than if they'd been available from the start).
    • Marble quarries go deeper as they're mined, but this is only a cosmetic effect and they remain an infinite source of stone no matter how deep they appear to go.
    • Silver and copper ore deposits never run out, but building more mine buildings will not necessarily produce those resources any faster, as there is a limit to the number of miners picking at an ore tile at a time.
• Civilization VI's Gathering Storm expansion reworks strategic resources to work like this. Each improved strategic resource gives you a limited quantity of that resource per turn, which is consumed when building or upgrading certain units, or passively by power plants and unit maintenance. By default, each strategic resource is capped at 50, but certain buildings and districts can increase the cap.
• Command & Conquer: Starting with Command & Conquer: Red Alert 2, in addition to slowly-replenishing ore mines, some maps feature oil wells that can be captured by engineers for slow but effectively unlimited income.
  • Command & Conquer: Tiberian Dawn: Tiberium (an Alien Kudzu-like crystal that leeches metals from the soil and concentrates them aboveground for easy collection) is slowly but continuously produced by "blossom trees". This even becomes a game hazard if allowed to proliferate, as Tiberium fields damage infantry that walk over them. The remastered version lets you select the rate at which Tiberium is spawned in multiplayer games.
  • Command & Conquer: Red Alert: Like Tiberian Dawn, Ore Mines continuously pump out ore on the ground. Gems give more credits when collected, but they don't respawn. The remastered version lets you select the rate at which ore is extracted in multiplayer games.
  • Command & Conquer: Generals: Every faction can get a secondary source of income (the Americans get supply drops, the GLA build Black Markets, the Chinese train hackers to steal money from web transactions) that's much slower than regular resource collection from supply depots, but unlike the depots, these will never run out unless destroyed, and can be built without limit (though they take a while to pay for themselves).
  • Command & Conquer: Red Alert 3: Collectors bring in ore from mines at 250 units per trip until the mine is depleted, at which point they only bring in 75 units per trip. The Allies can slightly increase the amount extracted per trip even when depleted.
    • Exaggerated in one Commander's Challenge map where the starting mine contains only a single load of ore and no other sources of income (named, fittingly enough, "Your Gold Mine Has Collapsed"). Players are given a larger-than-usual amount of credits at the start to make up for this.
• Dark Reign requires harvesters to collect water from springs, which is then sent to the Water Launch Pad and sold for credits. A spring refills at a fixed rate, slightly slower than what the water harvesters can handle.
• Dark Souls: Estus Flasks are infinitely refillable at Bonfires in the series, but you can only carry small amounts at a time.
• Dawn of War:
  • The main resource is Requisition, which is obtained by capturing Strategic Points around the map (up to a maximum of 400 per tick). These points can then be fortified with Listening Points, which increase the amount of Requisition obtained per second, but they eventually degrade, providing less Requisition over time.
  • Power is obtained by building Generators, with a limit of 6 generators per HQ building (and some factions limit the amount of HQ buildings as well) and Fusion Generators that need to be built over special Slag nodes. The total limit is 350 per tick. Regular generators can eventually degrade, but that can be circumvented by ordering them to self-destruct and building fresh ones.
  • The Necrons don't use Requisition, only Power. However, the more Obelisks they build on Strategic Points, the faster their units are built, getting a 20% production increase for every one (up to 100%). To prevent them becoming a runaway juggernaut (somewhat), every generator they build takes an increasingly long time to build.
• Don't Escape 4 requires you to continually refuel the car from the tanker at the petrol station if you are to continue using it, but the tanker will never run out.
• Dragon Quest: In the Zenithia trilogy (the games numbered IV, V and VI) the item Yggdrasil Dew, which fully heals the entire party's HP, can be obtained from a pool in Zenithia. This source never runs out, but the player can only carry one vial of the dew, needing to spend it before being given another one.
• The Dune franchise:
  • Dune II, Dune 2000 and Emperor: Battle for Dune has spice fields, which slowly deplete by being harvested but replenish through spice blows. Each field can only support so many harvesters, however, due to them getting in each others' way (and also provoking Sand Worm attacks). In Emperor, the Harkonnen Buzzsaw can churn spice fields, making the spice inaccessible to everyone.
  • Dune: Spice Wars: All on-map resources (spice, plascrete, water, thermal power, etc) are unlimited, but can only have one building harvesting from them that provides a certain number of resources per day. This makes planning your provinces (which can have a maximum of five buildings, some of whom have synergies that increase harvesting rate for each other) an important gameplay aspect. House Corrino can build duplicates of all non-spice harvesting buildings.
• Dungeon Keeper has gold tiles and gem tiles that the player's imps can mine for wealth. Gold tiles provides lots of wealth in a short time but are fully dug out after a few swings of an imp's pick, gem tiles cannot be destroyed and provide infinite wealth but at a slower rate than gold tiles.
• Dyson Sphere Program:
  • Most resource nodes are finite but their rate of extraction is only limited by how many miner modules you can put around them. Crude Oil nodes never run out but can only accept a single extractor per node. This was then subverted in a patch that put Crude Oil nodes under diminishing returns. The node will technically never run out but after some time it will produce oil so slowly as to be impractical.
  • Resources mined from gas giants (oxygen, deuterium and fire ice) are infinite but each gas giant is limited to 40 extractors that can extract each resource at a fixed rate.
• Earth 2150: Instead of mining credits like in single-player, they just arrive slowly out of nowhere in a multiplayer or skirmish mode. This gives a stronger advantage to Lunar Corporation players, who can deploy buildings anywhere without a builder unit.
• Empire Earth: While resource nodes are limited, they contain such large amounts (and can only be harvested by up to six workers) that they're functionally infinite but very slow to accumulate, meaning a player who doesn't expand to other resource nodes will find himself outgunned very quickly. The sequel outright gives them infinite quantities.
  • Averted with forage patches and animals which have intentionally limited resources, as the player is meant to build farms to gain food. The sequel features infinite food nodes, but still expects the player to build farms to supplement their income.
  • All games in the series have ways of increasing the efficiency of resource gathering:
    • In the first game, the amount of resources obtained per worker cycle can be increased by permanently staffing a drop-off building with workers, with a maximum of 50 doubling the amounts of resources dropped off at that building. The sequel makes it a smaller bonus and the workers aren't removed from the headcount.
    • One civilization has the ability to send seven workers per node instead of six.
    • Resource collection rates for individual resources can be increased via upgrades at the central building in the first game, and for basic or special resources via research points in the second.
  • The second game gives Markets and Docks the ability to generate gold through trade units that head to another trade building to drop off their cargo, generating more gold the longer the trade route. However, the speed at which gold is made is limited by the trader's unloading speed (and several upgrades reduce this downtime).
  • Often averted in campaign missions where resources are scarce but can be obtained by trade with another player or by destroying and raiding their buildings. The second game's Market building allows the player to exchange resources for gold, but the exchange rate increases/decreases very swiftly with every purchase/sale.
  • The second game has resources that become obsolete as they progress through Technology Levels: Tin is no longer needed after Saltpeter becomes necessary for firearms in the Renaissance, Iron is no longer needed after Oil becomes a commodity in the Industrial age, and Saltpeter is replaced by Uranium in the modern age. Not only do they still take up space on the map, workers can't harvest them anymore.
• Endless Sky: As a concession to novice players, the player's ship has Gradual Regeneration: hyperspace fuel ex nihilo, so it's not possible to become entirely stranded, except in special locations like the black hole at the centre of the galaxy. Theoretically, any tank can be completely filled this way. However, unless the player has a ramscoop installed, the process is so slow that they're likely to be ambushed and killed by pirates before recovering enough fuel to escape.
• Factorio: Most ore patches take so long to deplete as to be effectively infinite, with production limited less by the amount of ore available and more by how many mines will physically fit on the patch. Oil pumpjacks will produce oil forever, though the rate at which they do so slows down over time until it's not practical. Water is truly unlimited, as even a tiny lake completely surrounded by water pumps working 24/7 will never drain it.
• Fallout 4: Settlements will automatically generate food and water every 24 in-game hours, which is stored in the settlement's workshop. Each settlement has a cap on these resources based on the settlement's population; if the game detects food and water already stored in the workshop up to/exceeding the capped amount, no more will be produced until the player empties the workshop.
• The first Fantasy Quest game only allows you to take two carrots at a time from the vegetable field, although the supply of carrots never runs out. The sequel, which is a deliberate parody of the genre which mocks many of the unlikely situations from the original, allows you to take up to twenty onions at a time; upon reaching the limit, the game notes that "here are plenty more onions here — in fact the supply does not seem to be diminishing as you take more — but perhaps you have enough for now".
• Golden Sun:
  • The Water of Hermes fully heals a single character, but you can only carry one at a time. Using it requires returning to the Mercury Lighthouse to refill the bottle.
  • Each Lighthouse restores a small amount of Psynergy to its elementally-aligned character(s) every turn in battle, ensuring they'll never run out (although it's also restored slowly just by walking around). Commented on after the Mercury Lighthouse battle by Mia, as an explanation as to why the Mars-aligned Saturos' power was drastically reduced.
• Grand Theft Auto: San Andreas: CJ can acquire properties and has to personally go to these business to get the stored earned money, and these businesses cannot hold an unlimited amount of funds.
• Killer7: Thick blood (used to upgrade the titular assassins with more health and killing power) can be collected from any Heaven Smile shot at their weak point, and there's no limit to how much you can collect in a chapter; however, if you try processing too much at a save point, the blood machine will break down and be out of service for the rest of the chapter.
• The Legend of Zelda: Resources in the franchise are often carried in Empty Bottles, of which each game has a limited number to find. Many powerful Healing Potions and the like are free, but only found in out-of-the-way places that must be revisited each time the player wants to refill a bottle.
  • The Legend of Zelda: Breath of the Wild:
    • If the player has an abundance of elemental arrows then the shops won't stock more until the player runs low. However, normal arrows are almost always available for purchase regardless of player amount, and more elemental arrows can be acquired at any time from enemies carrying them.
    • Healing fairies will stop spawning if the player has more than 5 in their inventory. They can partially circumvent this by holding some of the fairies in hand.
  • The Legend of Zelda: Ocarina of Time: Healing fairies can always be obtained at fairy fountains in various locations around the world, but the number you can take with you into a dungeon is limited by the number of bottles you have found, the maximum possible being four.
  • The Legend of Zelda: Twilight Princess: After reaching the Great Fairy in the Cave of Ordeals, respawning fairies can be found in fountains to be bottled for use. 1 fairy per bottle. The Great Fairy will also grant you her Tears, which act as a Healing Potion that gives a Full Health Bonus, and also must be bottled.
  • The Legend of Zelda: The Wind Waker: The Elixir Soup fully refills Link's health and magic, and also makes him more powerful until he gets hit again. Two helpings fit in a bottle, but Link's grandma, who lives in the First Town on an island in the corner of the map, will only give him a refill if he doesn't already have at least one helping.
• Mass Effect: Both Mass Effect 3 and Mass Effect: Andromeda utilize various "boxes" that replenish resources (Ammo boxes first appear in 3, while Health and Shield refills first appear in Andromeda). Each, however, has a finite amount of their designated resource and only regenerates a set amount after a set time period. Thus, a player cannot simply camp next to them and gain infinite ammunition or health/shields. Averted, however, with the Forward Station in Andromeda, which automatically fills everything to max if the player is within proximity, but are also spread much thinner across the maps.
• Plants vs. Zombies: While the player can collect sun infinitely in a level, it only appears in increments of 25, 50, and 75. Considering most plants require at least 50 sun to plant, the player will spend it almost as soon as it's collected.
• Rise of Nations: The amount of resources an empire can harvest in a tick of time is limited, and several technologies increase this ceiling.
• Runescape:
  • Mineral resources like coal and copper are infinite, but the rocks they are found in need a certain amount of time to replenish before the player can mine from them again.
  • This is how most of the gathering skills (Mining, Woodcutting, Fishing, Farming, Hunter and the Runescape 3 exclusive Divination and Archaeology) work; under most circumstances, you'll only ever get one resource at a time from each node you harvest per game action. Certain equipment (such as the Varrock Armor for mining) can double your resources for certain actions, but these require deep time investment into the game to unlock.
• Throughout the Saints Row series, you may acquire real estate assets throughout their respective game worlds that subsequently generate money every few real-time minutes. However, said money is not transferred directly to you, but instead to your cribs, which you have to visit regularly to fetch it, as the amount the cribs can hold is capped and once the cap is reached, any additional income is forfeit. This mechanic becomes rather ludicrous from Saints Row: The Third onward, where can collect the income from anywhere by simply using your cellphone — but you still have to do so manually for whatever reason, and you lose any income above the cap if you neglect it.
• The Seven Deadly Sins: Grand Cross: Crates and barrels throughout the game world can be smashed open to retrieve gold and food ingredients. These crates respawn each 24-hour period, making them infinite resource generators that can only be accessed once per day.
• Starcraft:
  • Starcraft I: In the unit info tab at the bottom of the screen Vespene geysers display a large but finite amount of vespene gas (which is required for more advanced units and upgrades), but once they're "depleted", their output just drops sharply instead of running out. Workers collect 8 units of vespene gas while the gas counter is above 0, but once depleted can only extract 2 units per trip.
• StarCraftII: In contrast with the first game, once all of the gas is extracted from Vespane geysers they're completely exhausted.
  • StarCraft II: Wings of Liberty: One mission has industrial scrappers regularly deposit metal pickups that convert to minerals throughout the level, though these are no replacement for having actual workers collecting minerals.
  • StarCraft II: Legacy of the Void: Second prologue mission lacks vespene geysers, but frequently spawns vespene for you to pick up.
• Total Annihilation has metal collected at a rate based on resource collectors on metal deposits which never run out, while energy can be collected without limit by building a generator on any buildable ground. Some missions take place on metallic planets which allow metal to be mined anywhere, and has structures that convert energy to metal, both removing the limit.
• Transformers: Earth Wars: Alloy and energon, as well as omega energon, can be mined indefinitely. But there's only so much your harvesters can actually hold before the harvesters stop working. You can transfer the resources to the appropriate storage building, but they also have limited space determined by their level. If you try to transfer more of a resource than your silos have room remaining for, the excess is lost.
• In Universe at War, the Masari can generate energy from nothing instead of harvesting them, but are also the only faction with a cap on how much energy they can have.
• Valheim:
  • One game setting allows changing how many resources are dropped, up to half or triple the default, greatly slowing/accelerating progress since resources are only available by killing enemies, which respawn at a fixed rate.
  • No-cost building lets the player place buildings with no materials (as long as they've held the materials at least once, even separately). This also applies to vegetables and beehives, ensuring an infinite supply limited only by the surface of the cultivated land, its location, that by default a seed grows one vegetable and a vegetable gives three seeds (a beehive contains up to four honeycombs), and how well-protected it is against enemies.
  • Surtling cores (required to smelt metals) are first found sparingly in Burial Chambers, dungeons guarded by skeletons and ghosts. Once you reach the swamps, however, you can find geysers that continuously spawn surtlings. Surtlings being fire elementals that take damage on contact with water, it's quite easy to dig up the ground around a flamespout, ensuring that the surtlings die almost as soon as they spawn (and as a bonus, they drop coal, which is also needed to smelt metal) and making coal an infinite-if-slow resource.
• Warcraft III:
  • All factions but the Night Elves collect lumber by chopping down trees at different rates (10 per trip for the orcs, 20 for the undead and naga, 10 at the start for humans but upgradeable to 20 and then 30), which makes them take longer trips as the forests shrink and eventually run out (not to mention allowing entry into their base from undefended directions). The Night Elves don't damage the trees at all and so never run out, but Wisps harvest lumber at a much slower rate (5 per cycle).
  • Items and mercenaries are available in limited quantities (usually 3), and have a cooldown before they can be bought/hired again once depleted, but are never Lost Forever (except for Marketplaces, which produce items based on what creeps are dropping around the map and so refresh their inventory every few minutes).
  • The Goblin Alchemist's Transmute spell instantly kills an enemy unit and gives the player gold based on its cost, but is limited to weaker units and has a long cooldown.
  • The Orc Pillage ability gives the player resources with every attack made on an enemy building. While theoretically the player can live entirely off what the ability gives them (up to 3 gold and lumber per attack) or even leave enemy buildings standing so they can be attacked after being repaired, it's best used to supplement worker-provided income.
  • The Undead's Graveyard building continuously produces up to 5 Ghoul corpses which are used by the Undead as a source of animated skeletons or emergency rations for damaged Ghouls and Abominations. Meat Wagons can similarly be upgraded to produce Ghoul/Crypt Fiend corpses by themselves instead of having to collect them.
• Warhammer 40,000: Gladius:
  • While some resources, like ore, are theoretically unlimited (but extractors can only be put down by a city), the extraction rate goes down and even becomes negative due to unit upkeep costs.
  • Loyalty is a resource that determines the control the player has over their cities' population and their production output, going down by one for every new unit of population. Building a new city also automatically costs 6 loyalty to every city the player owns, limiting their expansion. And while Space Marines can continuously increase their loyalty via Chaplains, they can only build a single city.

Examples from other media:

Anime & Manga

• In Fate/kaleid liner PRISMA☆ILLYA, the Kaleidosticks are able to draw upon an effectively infinite amount of magical energy by drawing it in from throughout the multiverse. However, they're limited by the amount of energy their user is able to handle and use in one sitting. Illya bypasses this by using both Ruby and Sapphire at once and having them use her circulatory system as makeshift Magic Circuits in order to defeat Gilgamesh, but both sticks ban her from ever doing so again due to the risk of burning her organs out in the process.
• Mobile Suit Gundam 00: The Gundams GN Drives are able to produce GN Particles effectively indefinitely, but at a finite output such that Particle intensive applications leave them drained until they recharge their Particle reserves. There's also only five GN Drives meaning any GN tech not hooked up to the Gundams would have to eventually recharge from them.

Fan Works

• Dungeon Keeper Ami: Ami's gem furnaces create an effectively endless but slow rate of gem production, capped by the number of furnaces active at once.

Literature

• "A Poor Rich Man" by Leo Tolstoy has a poor man find a purse that produces a golden coin every time he reaches into it, but the catch is that he must throw the purse away before spending a single coin, or they will all turn into pebbles. The man becomes unable to throw the purse away because he keeps thinking his current stockpile of gold isn't enough to last him for the rest of his life, and he dies in utter poverty.
• Aesop's Fables: The Goose That Laid The Golden Egg: A poor couple finds a goose that lays a solid gold egg every day. Deciding that a single egg is not enough (in one version, they start living an absurdly expensive lifestyle that even the daily delivery of gold isn't enough to pay for), they kill the goose, thinking to find a huge treasure trove of gold inside, but find nothing, losing their source of free money in the process.
• The Castle of Lake Tchou-An (a Judge Dee Fan Sequel): The titular castle was built generations prior by a fisherman who attracted the good graces of the local river goddess, and his descendants have been rich ever since. The judge discovers the truth: a hidden grotto where a trickle of gold-laden water continuously pours forth into sieves, slowly accumulating a fortune. Unfortunately, this also caused the fisherman's descendants to become Idle Rich of the worst sort, unwilling to leave their domain for fear of any outsiders discovering the secret.
• Riverworld: The Mass Resurrection onto the Riverworld leaves humanity reliant on "grails", personal containers that can be activated up to three times per day to create limited quantities of food, drink, and other useful items. This leads to "grail slavery" where people are kept captive and forced to relinquish most of the yield of their grails.

Mythology & Religion

• Chinese Mythology: The gods need to eat the peaches of Xi Wangmu every so often to maintain their immortality.
• Classical Mythology: The gods need to eat the ambrosia of Hebe every so often to maintain their immortality.
• Norse Mythology: The gods need to eat the golden apples of Idunn every so often to maintain their immortality.

Tabletop Games

• In Ars Magica, mages can find small amounts of raw vis (solidified magic) in certain natural locations. When it is found and removed, it will be created again over a period of a year. This means it can be re-harvested each year.
• Monopoly has it written in the Rules that the Bank never runs out of money. If there isn't enough on hand, players may script their own bank notes to cover accounts receivable. However, the most money any one player can rake in during a single turn is $1000, and is usually closer to $400. The most money receivable from another player is $2000, as the fee for Boardwalk with a hotel.
• 7 Wonders and Seven Wonders Duel: Once a resource card is acquired it will provide the same amount of resources (one or two) at every turn. However, if these resources aren't used in the current turn, they don't carry over to the next turn, nor can they be sold or otherwise "stored".

Web Animation

• Strong Bad Email: In "pop up", Strong Bad's ideal pop-up book would include a mini-fridge that inexplicably summons an actual, edible hamburger patty every time that page is opened. Strong Bad calls the book "a source of unspeakable power" when he realizes he can create a theoretically endless supply of burgers with it.

Real Life

• Thought experiments designed to demonstrate the "Tragedy of the Commons" often involve a theoretically infinite resource that benefits everyone, but can only be harvested in small amounts, meaning those who use it must put the greater good of the community before their personal selfishness. The classic example is a village green where there is just enough grass for each villager to graze one of their animals at a time; it only takes one villager deciding to graze two animals at once before the grass is being eaten faster than it grows back.

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