Plague of Locusts

A swarm of locusts attacking a farm in Kenya, March 2020

Behold, the locust.

Alone? A simple and usually solitary short-horned grasshopper.

But when the conditions are right?

Well, first let's discuss what those conditions are. Following a phase of drought and rapid vegetation growth, locusts begin to breed rapidly, with the groups of nymphs developing into wandering swarms of winged adults - and it is in both forms that they become a Plague of Locusts.

During "swarming" behavior, both nymph and adult populations are known to cause serious damage to crops and fields by stripping them thoroughly. Adult locusts in particular are powerful fliers capable of traveling great distances - not only is the phenomenon unsurprisingly widespread, it's also Older Than Dirt. The earliest instances are dated back to the ancient Egyptians and prehistory, while relatively later works such as The Iliad and The Qur'an also make mention of locust swarms as well. Locust swarms are sometimes likened to large black "clouds" due to their sheer size.

The devastation of crops are a major factor in famines and human migrations as well as outbreaks of disease, to the point that locusts themselves are considered harbingers (if not carriers) of actual plagues. In fiction and literature, this connection has led to them being portrayed or symbolized as Walking Wastelands, almost always including making the insects inherently poisonous themselves. Funnily enough, locusts themselves have been used as a source of food - "bald locusts" are listed among acceptable food for Israelites as far back as the Book of Leviticus 11:22; in the New Testament, Matthew 3:4 and and Mark 1:6 assert that John the Baptist ate locusts and wild honey during his stay in the wilderness; and many modern cultures across Africa, West Asia and East Asia consider locust a delicacy.

A subtrope of The Swarm, and the phenomenon that its sister trope, Horde of Alien Locusts, was named for. Compare Termite Trouble, a similar depiction of insect pests as a troublesome devouring swarm.

Examples of Plague of Locusts include:

Anime and Manga

Near the end of the Yu-Gi-Oh! anime's fourth season, Dartz unleashes a swarm of locusts as he prepares to summon Leviathan.
In the English dub of the Yu-Gi-Oh! GX anime, Titan's "Terrorking Archfiend" uses an attack called "Locust Storm Barrage" in his duel against Jaden.

Comic Books

Marvel Comics has Dr. August Hopper, alias The Locust. An entomology professor from Metro College, he was fired for peddling radical approaches on the genetic manipulation of insects, and took up a position with Ryan Chemicals where he helped create improved pesticides. Believing that he was robbed of his due credit, he went insane and started researching ways to create super-bugs, with many of his attacks naturally employing giant crop-eating locusts. The Locust has since battled against the X-Men and the Hulk.
In Bone, locusts are a motif that play a major part in the series. A swarm of locusts occurs near the very beginning of the series, separating Fone Bone from his cousins. The swarm is implied to be connected to the enigmatic Hooded One, who commands an army of Rat Creatures and is the superior to their king. The Hooded One is in turn The Dragon and The Heavy to The Lord of the Locust, and is revealed to be the undead Briar Harvestar, whose body was resurrected and possessed by a swarm of locusts. Both the Lord of the Locust and believe Phoney Bone to be a key to their Evil Plan.
- The prequel comic Rose delves into the Valley's Creation Myth, where the Lord of the Locust's origin is shown. A nightmare spirit that desires to walk the Waking World, it sought to possess the Dragon Queen Mim, who kept the world in balance by holding her tail in her mouth - but the possession drove her mad, and the dragons turned her to stone, sealing them both beneath the Valley’s eastern mountains. In the then-present day of the main story, the Lord of the Locust manipulates Briar's jealousy of Rose to gain her servitude and engineer its release.

Film

In 1999's The Mummy, we get to see a horde of locusts descend upon "modern" Cairo as part of the ten plagues revisited upon Egypt with the release of Imhotep.
The Prince of Egypt showed a swarm of locusts during "The Plagues" musical number.
Locusts: The 8th Plague is a 2005 natural horror film about a group of farmers and scientists battling a swarm of flesh-eating locusts.
Locusts (called Locusts: Day of Destruction outside the US) is another 2005 horror film, featuring a swarm of genetically engineered hybrid locusts that are set loose and begin devouring crops across the United States.

Literature

The Day of the Locust is a 1939 novel by American author Nathanael West. Set in Hollywood, the novel follows a recent hire in young Yale Fine Arts student Tod Hackett, whose peer group comes to discover the lie of the American Dream. Originally titled "The Cheated", the chosen title reads as a deliberate homage to the destruction of Exodus, as observed by Susan Sanderson (e.g., Tod Hackett's painting entitled "The Burning of Los Angeles").

Music

Andrew Osenga has the single "The Year of the Locust", whose title is derived from Joel 2:25 where God promises to restore the years the locusts have eaten.
Ghosts VI: Locusts, the eleventh studio album by American industrial rock band Nine Inch Nails, was released as a free download on March 26, 2020 simultaneously with Ghosts V: Together. Reviews liken the album's sound and feel to its namesake insect swarm, calling it "unsettling", "anxious and anxiety-inducing", and "harrowing".
Unto the Locust is the seventh studio album by American heavy metal band Machine Head, released in September 2011; an advance mix of the first single "Locust" was released earlier in June.

Oral Tradition, Folklore, Myths and Legends

This trope has a special prevalence as one of many well-established Biblical Motifs; in addition to being an omen of future destruction, locust swarms are often invoked as a metaphor to describe nations of great number.
- Among the most notable, Exodus depicts a swarm of locusts as the eighth of the Ten Plagues that struck Egypt in Chapter 10:4. This is constantly referred to in the later books, such as the 105th Psalm.
- In Proverbs, the thirtieth chapter lists locust swarms as a demonstration of wisdom: "the locusts have no king, yet all of them march in rank".
- The entire first chapter of the Book of Joel (which is a three-chapter segment) foretells of "an invasion of locusts", which is a clear stand-in for the army of a powerful nation who will destroy Judah's prosperity. The following chapter makes a promise of restoration afterward.
- The Book of Revelation mentions a special kind of hybrid "locust" that more closely resembles armored horses with human heads and leonine teeth in Chapter 9, led by Abaddon/Apollyon, the "angel of the Abyss". Unlike typical locust swarms, these Abyss-summoned beings were forbidden from harming the plant life of Earth, but were given free reign to torment (but not kill) those who had not yet accepted God and Christ, as signified by the marks on the chosen's foreheads.

Tabletop Games

The Tyranids of Warhammer 40,000 fame are often likened to a terrifying plague of alien locusts. They travel the galaxy in Hive Fleets that are so incomprehensibly massive, they are made of lightyears worth of ships at their biggest. They descend upon planets and devour everything they can with a crazed, hungry fervor - and by "everything", we mean everything. Their rampages end with the targeted planet being stripped of all life and left a barren rock. You can kill millions, if not billions of the damned things and still lose, because they always have millions and billions more to throw at you. Furthering the comparison to an apocalyptic swarm of insects is that there's no properly defined leader: all Tyranids are governed by a ravenous hive mind that is so overwhelmingly savage and powerful that it's impossible for the setting's Chaos Gods to control or corrupt.
Yu-Gi-Oh! card game:
- "Swarm of Locusts" is an Effect Monster that can destroy a Spell or Trap Card when Flip Summoned, and can flip itself face-down once per turn (which lets you activate the effect more reliably).
- "Desert Locusts" is a Synchro Tuner Monster that is a group of much larger locusts, and has an that effect can facilitate "swarm" strategies with a quick Synchro Summon.
The board game Ankh: Gods of Egypt includes a "Plague of Locusts" card as part of every god's battle deck. Using it during a battle forces all participating gods to (secretly) bid followers, with the losers of the bid being wiped from the affected region, and all gods losing the wagered followers.

Video Games

If you donate a migratory locust to the museum in the Animal Crossing series, bug-hating curator Blathers will never miss an opportunity to freak out about their monstrous appetites and the famines that swarms of them have been known to cause throughout history. During seasons where they're active, they're among the most common bugs you can find in your town. Thankfully, they aren't a threat to your crops whatsoever and are content to harmlessly hop around all day.
Several NetHack variants - such as SporkHack, UnNetHack, EvilHack, and SlashTHEM - have the locust as an enemy monster which often appears in swarms and is capable of inflicting terminal illness on players, bringing down even the most seasoned of combat veterans unless they can avoid/cure the sickness and defeat the swarm quickly.
Dark Souls III has the Locust Preachers (also called White-Faced Locusts), human-insect hybrids that have a taste for human flesh. They have human-sized and small-sized variants, and three non-hostile Locust Preachers appear as NPCs.

Western Animation

In Courage the Cowardly Dog, King Ramses has an all-devouring swarm of locusts that signal his presence and hunt down thieves. The locusts wipe out the two cat thieves at the beginning of the episode, and are called in as his last plague - they destroy nearly the entire farmhouse and its surroundings, and take Eustace as well when he tries to re-claim the stolen slab.

Real Life

Some types of cicada are referred to as "locusts" due to their swarming behavior upon finally reaching their adult states after 13 or 17 whole years - or in the case of the specific genus Magicicada, their synchronous emergence from underground dwellings in tremendous numbers. However, they generally avert this trope, and in fact tend to have their own set of associated motifs.
The Australian plague locust is one of the most damaging agricultural pests on the island, with the first recorded swarm in 1844.
The desert locust is an international cross-continent pest that can cause widespread damage to crops, as they are highly mobile and feed on any kind of vegetation. There's been an ongoing upsurge in desert locust swarms since 2019.
The honey locust or thorny locust is an aggressively invasive species of tree - normally native to North America, it has been introduced worldwide and is considered a major invasive environmental and economic weed in Australia. No points for guessing where the name came from.