Spiders (also known as Bau or Assault Spiders) are a common enemy in the Earth Defense Force series, first appearing in Global Defence Force. They are fast, agile enemies that fill the role of shock troops. In Earth Defense Force 2025 a new species of spider, the Retiarius, is also introduced.
Note: Those who are afraid of spiders may want to stop clicking on pages titled "Spiders."
Global Defence Force
The Bau is a giant creature that looks similar to a spider. It jumps around and shoots out strong, acidic thread, which not only burns through armor, but ensnares prey.
Global Defense Force Tactics
Spiders reappear in Global Defense Force Tactics, this time known as Giant Bau. These units are utilized as dual purpose anti-air and anti-ground troops.
Unlike earlier and later subtypes, the Giant Bau is only capable of firing its webbing 5 times before its glands will not produce any more silk, effectively making them the least dangerous of all subtypes. They are not great at dodging (perhaps due to the time it takes the various spiders to build up enough force to leap), but have a decent ability to directly hit their opponents with their web strands.
Earth Defense Force 2017
In EDF 2017, Spiders are a swarm type enemy that tend to jump after their targets. They shoot an acidic web at their targets. They come in two varieties, the regular Assault Spider and the large and very deadly King Spider. Their webs can shoot through walls on higher difficulty levels and they can spawn from UFO's or Bug Holes. In addition, fired webs remain in play for a few seconds, damaging and slowing those who try to move through them.
The Assault Spider appears in the first half of the game. They are very deadly and move around by jumping from place to place. They are very frail and rely on their numbers and webbing to take out opposition.
The King Spider is a much more capable opponent. They shoot out a huge amount of webbing that can do grievous amounts of damage to opponents. Your priority should be to take them out as quickly as possible.
Earth Defense Force: Insect Armageddon
In EDF: IA, Wolf Spiders are a deadlier foe than their counterparts in 2017, first appearing in Chapter 1 Mission 2: Firebase Clyde. They still shoot acidic webs but they can now use their fangs at close range to inflict serious damage. Their webs will also slow down a character, this is especially noticeable to a Jet soldier and can lead to being swarmed. They can also knock characters over by jumping on them. They come in two varieties, the regular organic version and the tougher and deadlier mechanical version.
Wolf Spider (Stage 1)
The Wolf Spider is the first stage spider encountered in the game. They are generally weak and rely on sheer numbers to overwhelm the opposition.
Biomechanical Spider (Stage 2)
The biomechanic spiders are the second stage. They are much stronger than Wolf Spiders and they have slightly different yet more deadly attacks. They have a single red Ravager eye.
- See main article: Tickers
Tickers are smaller arachnids that appear in swarms and can be spawned by Bomber Spiders. They are fast and agile, often seen rolling around to get behind an individual to latch onto them. If they succeed in latching on to a character they will start to pulsate and after a while explode dealing damage, with the time to explosion related to the difficulty level. An action prompt will appear to remove an attached Ticker before it blows up.
- See main article: Bomber Spider
Bomber Spiders are enormous and more than a little disgusting creatures that function primarily as a spawner unit, with their main means of attack being to shoot out orange projectiles from their abdomen which "hatch" into Tickers when they hit the ground. Their only direct means of attack is a well-telegraphed and fairly slow straight-line charge, though due to their massive size this can still be tricky to avoid. They have a lot of health and engaging them is a high priority to stop the constant flow of Tickers. On death, a Bomber Spider will explode and spawn an additional 8-10 Tickers.
EDF 2025 / 4.1
Spiders are the third enemy introduced in the two games after Ants and the new Retiarius, and are one of the most common enemies in them. Like Ants, they are the size of a small building, standing around twice as tall as a human. They first appear in mission 6: Underground Cave, where it is revealed that they have spawned in the massive insect hive. The EDF seems to have forgotten they exist since the war eight years earlier, and suffer so many casualties they are forced to abandon their assault and focus on destroying the "new giant insects" as they come to the surface in the next mission, Eruption, using the firepower of the Artillery Team and the Heavy Support Aircraft Whale. It is implied that they are the forerunners of Hornets, since the giant hive is full of spiders, and Hornets actually use the Spider AI to move around when they are on the ground inside tunnels, with the same ability to leap.
Spiders are fragile but powerful "glass cannon" enemies, and are very agile, able to move by either crawling or leaping; they will often leap past the player character in an attempt to attack them from behind, and tend to attack from multiple directions at once. Like ants, they can climb on any surface, and can also jump to walls and tunnel ceilings. They crawl much more slowly than ants, and tend to prefer to jump whenever they are able to.
Their only method of attack is to lift up their abdomen and unleash a spread of silk threads, which fly forward until they encounter an obstruction and briefly anchor to it, swaying a little as they are pulled taut. The strands are flexible and anchored to the tip of the spider's abdomen, and will move if the spider does. They disappear after a while, but will damage NPCs and player characters if they contact them at any time while they are still "live." A spider thread becomes "used" if it strikes anything but terrain, however, so a character cannot be hit by the same strand multiple times and if strands hit a dead enemy they will be unable to deal damage at all (but will often thrust the corpse violently forward and then pull them back again). If the Spider is killed, any threads it has deployed will immediately become "used."
Each impact from a thread will also slow a player character down somewhat, with being hit many times effectively immobilising them even if they roll.
The number of strands of thread varies depending on the difficulty, from just three or four on Easy to around sixteen on Inferno. Regardless of difficulty, at medium range the large gap in the centre of their field of strands becomes character-sized, and often it is possible to avoid damage entirely by standing still. They are one of the only bugs that is effective against aircraft, since most are slow, though they will usually miss a Wing Diver since their silk strands take time to extend.
As the difficulty increases, Spiders also become tougher, faster and deal more damage. In addition, they attack sooner on coming within range (on Easy they will pause for a moment before attacking even if their target is right in front of them, on Inferno they attack the instant they are in range), and attack more frequently.
Spiders are at their most powerful in underground levels, where their threads can easily affect an entire corridor at once and they can quickly move great distances using long, shallow jumps that end with them attached to walls or ceilings. Missions like Charge Phase 2 where spiders come from multiple directions at once are particularly dangerous. It is also particularly difficult to deal with a Transport Ship or Tunnel Exit that is spawning Spiders, since it involves fighting a lot of fast, dangerous targets and one very tough one at the same time. Poorly planning such an assault can lead to Storm Team ending up right among a group that are not pleased with the prospect of losing their home and having to become hobo spiders.
Since spiders are individually weak, fast, travel in large groups and have superior range to Ants, it is best to combat them with mid-range rapid-fire or spread weapons such as the Ranger's assault rifles and shotguns, the Wing Diver's Thunder Bow, the Fencer's Hand Gatlings, or the Air Raider's ZE-Gun turrets. The Naegling Self-Propelled Rocket Launcher, Armored Vehicle Grape and most BM03 Vegalta variants are good vehicle choices, and a BMX10 Proteus will allow a team to see off an army of spiders with little trouble. Multi-lock weapons like Fencer High-Altitude Impact Missiles and the Ranger's Emerald rocket launchers are also very effective at range.
The Fencer can also redirect any Spider's threads with his Shield. The timing on this is a little tricky since it can only be done while the threads are still airborne; if they have already hit something they cannot be reflected afterwards.
They tend to move in more spread-out groups, making single-shot splash damage weapons less effective than they would be against Ants, though very broad spread weapons like howitzer Artillery Team strikes, the Vegalta Buster Arms' Dispersal Howitzers and the Ranger's Stampede grenade launchers are still very effective at range. The worst weapon choices are slow single-shot weapons like sniper rifles. Burst-firing explosive weapons such as multi-shot Wing Diver Plasma Cannons and the Ranger's Volcano-series rocket launchers are also a poor choice if the Spiders get close, since individual Spiders will often suddenly jump right in front of the player characters and kill them with their own splash damage.
Threads no longer shoot through walls intentionally on higher difficulties, though there are some areas of glitchy level geometry in the tunnel maps that spiders can shoot through. These areas are tightened up, though still partially present, in 4.1.
They have one Mutant variant:
The Silver Spider is a super-tough species with a gleaming silver body and purple eyes which actually first appeared in extra missions added to the Japan-only PSP version of Global Defence Force. In EDF 2025 they only appear in DLC, first being seen in DLC2: Mutant Rampage, while in 4.1 they are added to normal missions on higher difficulties. In 4.1 they first appear in Charge Phase 2 on Hardest or above, and will appear in Demon Army even on Hard.
They are essentially the inverse of the Gold Ant in terms of how they have been altered; their health boost is enormous, while their damage boost is relatively low. They fire more strands of thread that deal more damage, but not enormously more. Since they take a lot of time to kill, they are best fought with weapons that will stunlock them, such as the Ranger's Super Acid Gun, flamethrower and Flame Geyser weapons, the Wing Diver's Idunn electricity cannons, or the Fencer's Flame Revolvers. Air Raider tactics tend to involve shooting them with vehicles, though in tunnel missions the main tactics involve forcefield walls and Limpet Splendor multi-flechette launchers. Unlike their regular cousins, it is not a good idea to use multi-lock weapons: few do significant damage unless over-levelled for the current difficulty, and so are ineffective since the spiders will quickly close range with the character using them.
A Fencer's shield is still effective against them; hitting a Silver Spider with the full force of its own attack will typically kill it instantly.
Silver Spiders are an excellent source of items, usually dropping 2-5 on death, more than even a Red Drone in 2025 (though these drop up to 7 in 4.1). Mission 16 of 2025's DLC 2 (mission 21 of 4.1's DLC 1) Golden Darkness is particularly well-known for its usefulness as an item farming mission, since it contains many Silver Spiders and is relatively easy for a Wing Diver with a good Idunn weapon to beat even on Inferno, with split-screen co-op being used to bring along other classes to pick up the weapon crates.
Main article: Retiarius
This spindly spider first appears in Mission 4: Setting Sun. They are much larger than regular spiders and are unable to jump, instead crawling over surfaces. They are quite slow and tend to remain fairly stationary, usually occupying tough orb web structures spun between buildings. On the ground they will trundle around aimlessly, usually just walking in vague circles. Any building which has a Retiarius web anchored to it is invincible, so destroying them to bring down the web is not possible.
They attack with a similar thread-casting attack, this time cued with a "throwing" action of the spider's forelimbs: their thread is heavier and has thicker strands, and is thrown in an arc. Retiarius is more or less the "sniper" of spiders and has much greater range for its thread attacks than standard spiders. As with a normal spider, the strands will anchor themselves to the ground when they land and remain "live" for some time before disappearing; unlike a regular spider's threads, a Retiarius thread remains "live" until it disappears, and multiple characters can be hit by the same strand; however, it can only hit a second character if that character touches a point on the strand between the Retiarius and the character it is already pulling in; any part of the strand behind the pulled character is "used." Also unlike regular spiders, Retiarius will happily cast their threads straight through any obstruction, including firing them through their own web from the back. Like a normal Spider's attack, the number of threads fired in a single attack increases with the difficulty level.
If this attack connects, the character it hits will not just take a single hit; they will instead be trapped by it. A trapping strand flashes red and deals constant damage to any character caught in it with the frequency of these hits depending on the difficulty level, while they are slowly pulled towards the Retiarius that cast the thread. They are still able to move in any direction but away from the Retiarius that has caught them, though their movement is slowed dramatically.
If a Retiarius fully pulls a character in, they will shoot them at point-blank range with their thread, dealing enormous damage; if they are standing on a web, they will also drop the character into it. Being stuck in a web also deals constant damage, and can only be recovered from by destroying the web. A web's health appears to be scaled to its size, with the one strung over most of the city in mission 60 (63 in 4.1) Breaking Through being particularly durable. Webs will sway around if shot, and can actually catch characters when they are doing so (particularly if they are "freaking out" as they sometimes do when hit by artillery), but shooting them a few times should reset them. The NPC pathfinding system does not recognise the existence of webs, and NPCs will walk straight into a ground-level web if it is in their path.
In 2025, the only way for a character to free themselves from a strand is to kill the trapping Retiarius, while in 4.1 the Retiarius will release a victim if it takes significant damage. It is not possible to escape by entering a vehicle encountered while being dragged; the "get in" function is disabled. Being in a vehicle offers complete protection, however, with the Retairius only dealing one-off damage when the thread initially strikes the vehicle as a normal spider would. The strand does not stick to the vehicle and become "used," though, so touching it again will deal another hit. It is also impossible for a vehicle to become trapped in a web.
As with normal spiders, a Fencer can reflect a Retiarius' threads back at it. Since the Retiarius has a lot of health and deals damage in small chunks this is not as devastating as it would be against a normal spider, though it is a good way to avoid being ensnared if the Fencer is in the middle of the field of threads. Sadly, a Retiarius is not stupid enough to try to pull itself in if it is hit by its own threads, and so cannot be trapped by reflecting its attacks.
Normally they are only encountered in above-ground missions, the main exception being online mission 33 (34 in 4.1) Dark Prisoner, where a series of Retiarius webs are encountered at the top of a large chamber of the underground hive.
There is one Mutant variant of the Retiarius:
The purple version only appears in DLC for EDF 4.1, first appearing in DLC 1: Time of the Mutants. They are tougher than a regular Retiarius and throw a broader spread of threads with more strands.
These massive spiders first appear in mission 54 (57 in 4.1) Bug King, where four of them are menacing the city. They are scaled-up and have red eyes, and their thread attack uses thicker strands. A King Spider's attack has twice as many strands as a regular one's, and each strand does three times more damage. Like Queen Ants, despite their size they are not much slower than regular spiders, though they cannot jump the same height relative to their size, instead jumping about the same height as a regular spider.
The density and area of effect of their thread attack makes them one of the most fearsome anti-air enemies in the game, easily able to bring down a helicopter and difficult for even a Wing Diver to avoid. They will also attack at much greater range than a normal Spider.
A King will flinch every time it takes 4% of its total HP in damage, which will interrupt any animation it was previously performing: powerful weapons can stunlock them and prevent them from attacking. If the attack that caused the flinch was explosive, the King will be knocked into the air: once it is in this state, it ragdolls as if it weighs as much as a regular spider, and can be propelled ridiculous distances by follow-up attacks.
Due to this, they have an amusing tendency to propel themselves into the sky when defeated.
They have one Mutant variant:
Silver King Spider
Like the regular Silver Spider, this silver-bodied, purple-pink-eyed mutant receives a mediocre damage boost coupled to an enormous health boost. It also only appears in DLC for 2025, first appearing in DLC 3's mission King of Armor. Unlike other Mutants, it does not appear before this mission (now in DLC2) on higher difficulties in regular missions of 4.1.
Earth Defense Force 5
Aggressive Alien Species Beta
The basic Spider variant from returns as a common enemy in Earth Defense Force 5, under the name Aggressive Alien Species Beta (or Species Beta for short). The Spiders appear early on in the game, often accompanying Black Ants, and reappear throughout the following missions. As in previous games, the Spiders attack by firing silk strands containing a potent acid at enemies, which slow characters down and eat away at their health. Spiders move by either crawling slowly across the ground or by leaping into the air and covering larger distances quickly.
They are now slightly less vulnerable to having their attacks reflected by a Fencer, due to a change in the behavior of reflected strands. In 2025 and 4.1, reflected stands behaved exactly as if the Spider had fired them itself, dealing damage along their entire length: in 5, only the tips of reflected strands deal damage.
Silver Mutant spiders tend to appear in Spider-heavy missions on Hardest and Inferno: as before, they deal more damage and fire more strands of web, but their main trick is their hugely boosted health, around 20,000 on some Inferno maps. As before, they will always drop multiple items on death. They appear on lower difficulties in DLC missions.
- Main article: Retiarius
Another spider variant featured in the game is the Retiarius, now inexplicably called Aranea. Like before, Aranea perches atop webs that are pre-placed at the start of a mission, and casts forth strands of webbing to capture enemies and draw them to its web. This web does more damage than that of the basic Spider, and the player must injure the Aranea in order to break free. Unlike 2025 and 4.1, the web is now stopped if it hits intervening objects, and generally cannot be cast through scenery or terrain. They also cannot drag a character against a building or surface until they die anymore: instead, if the character they have trapped fails to move towards them for a set number of pulls (around ten), they will be released.
The King Spider also makes a return in EDF 5, simply called a King. With a body length of around 50 meters, the King is all-around a much more powerful variant of the basic Spider. The King attacks in much the same way as its smaller brethren, but the threads it fires cover a larger distance and deal greater damage.
Silver Kings are no longer as shy about actually being in the game, and will generally be thrown in on Hardest and Inferno in any mission that previously had a regular King. As with their smaller brethren, Silver Kings have a moderate boost to damage and strand count, but a major one to their HP, which can be around 360,000 on some Inferno maps.
- The distinctive large, forward-facing eyes show that the normal Spider seen in most games is based on a jumping spider (Salticidae). A very similar-looking species is found in Japanese houses.
- The spider seen in Insect Armageddon is closer in appearance to a Wolf Spider (Lycosidae).
- The Bomber Spider's grody abdomen is based on the back of a female Surinam Toad (Pipa pipa), which is a special spongy structure which partially envelops her eggs until they hatch disturbingly.
- The Retiarius is a Golden Silk Orb-Weaver (Nephila), probably based on the Japanese Jorō Spider (Nephila clavata). While there are net-casting spiders (Deinopidae), these spin a web between their front legs and grab prey in it with a fast lunging motion rather than throwing it as such.
- In 2025 and 4.1 the Spider thread effect and mechanics are also used by the Air Raider's wiregun weapons, though their thread acts like a Retiarius' attack, being thrown in an arc and able to score multiple hits with the same line.