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Automatically generates piles of Road Spikes on the nearby track. Excellent last line of defense.
~ Bloons TD 6 Description

The Spike Factory is a tower that makes its first appearance in an update of Bloons TD 4 on September 8, 2011. It makes a return in an update of Bloons TD 5 Flash on the March 13, 2012 update, and later elsewhere in the rest of the BTD5 generation games. It returns once more since the initial release of Bloons TD 6, on June 13, 2018, and is categorized as a Support Monkey.

The main role of the Spike Factory is to produce spike piles across its range to pop bloons. In this way, many of its upgrades serve in primarily cleanup roles. In addition, the Spike Factory can pop camo bloons by default, making it an effective option at countering early-game camo bloons.

Game appearances[]

Spike Factory makes up to 10 appearances:

Bloons TD 4[]

Main article: Spike Factory (BTD4)

In Bloons TD 4, the Spike Factory makes a debut. It was the second new tower to be released in Bloons TD 4, the third being Beekeeper only on Bloons TD 4 Mobile. The Spike Factory automatically generates spikes nearby.

Bloons TD 5[]

Main article: Spike Factory (BTD5)

The Spike Factory makes a return in Bloons TD 5. It first appeared in a later update of Bloons TD 5 Flash. Spike Factory now has even more upgrade options for increasing its power against specialized bloon types. It also has received many changes in both versions of Bloons TD Battles in different ways.

Bloons TD 6[]

Main article: Spike Factory (BTD6)

Initially the only offensive Support Monkey, the Spike Factory produces spikes on the bloon track. It was initially released with the release of the game. The core upgrade path structure for the Spike Factory has remained fairly the same when it was first released, with additional upgrades added for even more specialization.

Tower Costs[]

Game Easy Medium Hard Impoppable
Bloons TD 4 $595 $700 $755 -
Bloons TD 5 $640 $750 $810 -
Bloons TD 5 Mobile $640 $750 $810 $900
Bloons TD Battles $750
Bloons TD Battles Mobile $600
Bloons Monkey City $TBA
Bloons Monkey City Mobile $TBA
Bloons TD 6 $850 $1,000 $1,080 $1,200


Bloons TD 4[]

Before being upgraded, the Spike Factory shoots out clumps of five tacks at a rate of one shot nearly every three seconds (per second if fast-forwarded). These clumps always land in corners and disappear at the end of each round. If the Spike Factory is not placed in range of a corner, then the Spike Factory will act as if it is not in range of the track at all, and shoot spikes randomly in all directions. This tower will shoot randomly in its range and will not aim for bloons.

Faster Production
COST: $595 / $700 / $755
Description: Makes the factory produce spikes much faster.
Effect: Self-explanatory
Bigger Stacks
COST: $510 / $600 / $650
Description: The factory creates double size spike stacks.
Effect: Self-explanatory
White Hot Spikes
COST: $295 / $350 / $380
Description: White hot spikes can pop Frozen and Lead Bloons.
Effect: Self-explanatory
Spike Storm
COST: $5,950 / $7,000 / $7,560
Description: Every 15 seconds the factory generates a storm of short-lived spikes, filling up the entire track.
Effect: Self-explanatory

Bloons TD 5[]

In Bloons TD 5, all upgrades have gained two separate paths of four upgrades. Path 1 refers to the left side of the upgrades, while Path 2 refers to the right side of the upgrades.

The base Spike Factory dispenses spikes every ~2.3s. These spikes will last for up to 70 seconds (20 seconds in BTDB Mobile) and will last until used up or expired. Alongside Ninja Monkey and Dartling Gun, Spike Factory can detect and pop Camo Bloons by default. There is no limit to how many spikes are on screen, but with the lifespan mechanic in place, spikes do not last forever, unlike in BTD4. The presence of many spikes on screen can cause lag, however, regardless of game.

With the correct upgrades, the Spike Factory is a very versatile tower, and it becomes more true in Bloons Monkey City, due to the extra cash provided at the start of each game, accompanied by the Spike Factory's potential to stockpile high-pierce spikes versus the earlier stages of the game. It can be further upgraded to deal even more damage to Ceramics and MOABs through the Spiked Ball Factory and MOAB-SHREDR upgrades, respectively, allowing it to support other towers in later stages of the game. The final two Tier 4 upgrades, Spiked Mines and Spike Storm, all are useful at combatting larger groups of bloons, and can even handle with chipping down MOAB-class bloons decently. Unlike Ninja Monkey or Monkey Buccaneer, it is not dependent on Monkey Intelligence Bureau to pop leads.

Path 1[]

Bigger Stacks
COST: $595 / $700 / $755 / $840
Description: Generates larger piles of spikes per shot.
Effect: Self-explanatory
White Hot Spikes
COST: $765 / $900 / $970 / $1,080
Description: Cuts through lead like a hot spike through... lead.
Effect: Self-explanatory
Spiked Ball Factory
COST: $2,040 / $2,400 / $2,590 / $2,880
UNLOCK: 6,500 XP
Description: Modified to produce heavy but viciously sharp spiked balls instead of regular spikes. Do extra damage (3x) to ceramic bloons.
Effect: Self-explanatory
Spiked Mines
COST: $11,900 / $14,000 / $15,120 / $16,800
UNLOCK: 23,000 XP
Description: Rigged with heavy explosives, the spiked balls are set to go off when then they lose all their spikes.
Effect: Self-explanatory

Path 2[]

Faster Production
COST: $680 / $800 / $865 / $960
Description: TBA
Effect: Self-explanatory
Even Faster Production
COST: $1,060 / $1,250 / $1,350 / $1,500
UNLOCK: 2,000 XP
Description: TBA
Effect: Self-explanatory
COST: $2,550 / $3,000 / $3,240 / $3,600
UNLOCK: 7,000 XP
Description: TBA
Effect: Self-explanatory
Spike Storm
COST: $5,525 / $6,500 / $7,020 / $7,800
UNLOCK: 63,000 XP
Description: TBA
Effect: Self-explanatory

Total Costs[]

Bloons TD 6[]

Akin to prior installments, the Spike Factory shoots out clumps of five tacks at a rate of one shot in 1.75 seconds. Compared to other towers that transitioned from Bloons TD 5 to Bloons TD 6, the Spike Factory is one of few that has both its original upgrade lines intact.

Path 1 is primarily based upon making stronger spike piles. Bigger Stacks increases number of spikes per pile from 5 to 10 (or 50 to 70 with Perma-Spike). White Hot Spikes allows popping of any bloon type, including Frozen and Lead, increasing power of spikes further. Spiked Balls (returns from Spiked Ball Factory) replaces usual spikes with spiked balls, dealing even more damage to all bloon types while further increasing pierce, especially versus Ceramics and Fortified. The Spiked Mines upgrade adds powerful explosions into each spiked ball that activate upon depletion. The new Tier 5 upgrade surpassing the upgrade now creates even more powerful mines at a much slower rate, capable of wiping out crowds of stronger bloons with ease.

Path 2 focuses on aggressive production, starting with faster production with its first two upgrades, Faster Production and Even Faster Production, and then leading to MOAB SHREDR (returns from MOAB-SHREDR Spikes) for increased damage to MOAB-class, and its final upgrades Spike Storm and Carpet of Spikes increasing the Spike Factory's potential for widespread area damage. The Carpet of Spikes upgrade bases upon the old Spike Storm upgrade from BTD4 by making each spike storm automatic while dealing even more damage overall.

The new Path 3 is a more tactical one, providing a variety of utilities that improve spikes overall. This includes providing increased area of coverage to a targeting priority to spikes that last longer before timing out and even pass over to the next round. Long Reach increases the range of the Spike Factory and increases lifespan of spikes. Smart Spikes (formerly named Directed Spikes) adds target priorities to the Spike Factory, increasing its reliability on multi-lane maps, and adds a brief but quick boost of attack speed whenever a round begins. Long Life Spikes takes the long lifespan spike further by allowing spikes to carry over rounds and last even longer on the track. Deadly Spikes increases the round lifespan further and deals extra damage. Perma-Spike takes the spike longevity concept even further by manufacturing high-damage spikes with very long lifespan but at a much decreased production speed.

Spikes by default last for 1 round or 50 seconds, whichever comes first. These spikes will last even longer with Long Reach, Long Life Spikes, Deadly Spikes, and Perma-Spike upgrades. With Long Life Spikes, each spike pile will last for 2 rounds or 150 seconds, whichever comes first. Deadly Spikes increases the spike pile duration to 3 rounds or 150 seconds, whichever comes first. For Perma-Spike, each spike pile will last for 3 rounds or 300 seconds, whichever comes first.

Items for the Spike Factory are available in the Trophy Store. The "Spike Factory Pineapples" cosmetic changes the Spiked Balls, Spiked Mines, and Super Mines so that they resemble Exploding Pineapples.

Spike Factory is classed as a Support Monkey.

Path 1[]

Bigger Stacks
COST: $680 / $800 / $865 / $960
Description: Creates larger piles of spikes per shot.
Effect: Spike piles have 10 pierce instead of 5. For Perma-Spike, gains +30 pierce.
White Hot Spikes
COST: $510 / $600 / $650 / $720
Description: Cuts through Lead Bloons and Frozen Bloons.
Effect: Self-explanatory
Spiked Balls
COST: $1,955 / $2,300 / $2,485 / $2,760
UNLOCK: 2,400 XP
Description: Produces spiked balls that do extra damage to Ceramic and Fortified bloons.
Effect: Spiked balls deal extra damage to all bloon types, especially versus Ceramic and Fortified.
Spiked Mines
COST: $8,075 / $9,500 / $10,260 / $11,400
UNLOCK: 15,000 XP
Description: Spiked mines explode violently when they lose all their spikes.
Effect: Spiked mines deal even more damage to Ceramics and produce high-damage explosions upon depletion of a spiked mine's spikes.
Super Mines
COST: $138,125 / $162,500 / $175,500 / $195,000
UNLOCK: 32,500 XP
Description: Creates gigantic exploding spiked mines that can wipe out almost anything.
Effect: Reduces production speed to every 3.5s. Super mines create explosions every time a spike wears out and produces extremely high damage explosions once the super mine fully depletes its spikes.

Path 2[]

Faster Production
COST: $510 / $600 / $650 / $720
Description: Rapidly increases production rate.
Effect: Produces spikes +25% faster (0.80x attack cooldown).
Even Faster Production
COST: $680 / $800 / $865 / $960
Description: Increases production rate even more.
Effect: Produces spikes +42% faster (0.70x attack cooldown).
COST: $2,125 / $2,500 / $2,700 / $3,000
UNLOCK: 2,500 XP
Description: Super-Hard-Rending-Engine-Driven-Razors shred MOAB-Class Bloons.
Effect: Spikes deal +4 damage to MOAB-class bloons.
Spike Storm
COST: $4,250 / $5,000 / $5,400 / $6,000
UNLOCK: 11,000 XP
Description: Spike Storm ability: Shoots out a thick layer of spikes over the entire track.
Effect: Ability produces a wave of at least 200 spikes over the entire track. Ability behavior modifies with the Smart Spikes upgrade.
Carpet of Spikes
COST: $34,000 / $40,000 / $43,200 / $48,000
UNLOCK: 35,000 XP
Description: Regularly sets a carpet of spikes over the whole track.
Effect: Every 15 seconds, produces an automatic Spike Storm. Spikes also deal more damage to bloons.

Path 3[]

Long Reach
COST: $125 / $150 / $160 / $180
Description: Increases range for spike pile drops, plus piles last longer.
Effect: Increases range of the Spike Factory, and ordinary spike piles last for 100 seconds instead of 50 seconds. Spike Storm ability spikes last for 30 seconds instead of 20.
Smart Spikes
COST: $340 / $400 / $430 / $480
Description: Spike Factory gains special targeting priority and accelerated production at the start of each round.
Effect: Gains the Close, Far, and Smart target priorities. In addition, attacks 4x faster for the first 2.5s of a round.
Long Life Spikes
COST: $1,190 / $1,400 / $1,510 / $1,680
UNLOCK: 2,100 XP
Description: Spikes last much longer and can carry over one round.
Effect: Spikes last for 140 seconds instead of 100 seconds, and carries over 1 round.
Deadly Spikes
COST: $2,975 / $3,500 / $3,780 / $4,200
UNLOCK: 9,000 XP
Description: Extra deadly spikes can pop through 2 layers per spike and last another round.
Effect: Spikes deal 2 damage each and last for 3 rounds instead of 2.
COST: $25,500 / $30,000 / $32,400 / $36,000
UNLOCK: 29,500 XP
Description: High damage spikes become almost permanent.
Effect: Reduces production speed to every 4.85s. Spike piles have 10 damage per spike, 50 pierce per spike pile, lasts 4 rounds instead of 3, and lasts for 300 seconds instead of 140.

Total Costs[]

Differences between BTD5 Flash and BTD5 Mobile[]

  • Nerf Spike Factory and its upgrades have a slower attack speed.
  • Buff Spiked Balls pop more bloons (16 → 20).
  • Nerf Spiked Mines have smaller explosions and pops less bloons (20 → 16).
  • Buff Spike Factory produces one pile of spikes immediately upon placement, instead of delaying for a few seconds.
  • Nerf Spiked Mines do not explode when they disappear after time.

Update History (Bloons TD Battles Mobile)[]

The Spike Factory's been noticeably buffed via game updates in the form of price reductions to its upgrades and itself. Despite this however, it continues to be one of the least used towers in the game along with the Glue Gunner and the Sniper Monkey, due to how heavily it struggles versus grouped bloons. The only loadouts that use the Spike Factory are Engineer Farm Spike Factory, Boomerang Farm Spike Factory, and Tack Farm Spike Factory.

Due to prevention of lagging other players' devices, Ninja Kiwi has nerfed the Spike Factory to produce much less spikes than normal by decreasing its spike pile lifespan dramatically.

Initial Release
  • Nerf Spikes have a much shorter lifespan (70 seconds → 20).
  • Buff White Hot Spikes price decreased ($900 → $600).
  • Buff Spiked Ball Factory price decreased ($2400 → $2200).
  • Buff Spiked Mines price decreased ($14000 → $12000).
  • Buff Spike piles no longer spawn onto unused track in Defend Mode.
  • Buff Tower price decreased ($750 → $700).
  • Buff Faster Production price decreased ($800 → $700).
  • Buff Even Faster Production price decreased ($1250 → $1150).
  • Buff Tower price decreased ($700 → $600).
  • Buff Bigger Stacks price decreased ($700 → $550).
  • Buff White Hot Spikes price decreased ($600 → $500).
  • Buff Faster Production price decreased ($700 → $600).
  • Buff Even Faster Production price decreased ($1150 → $900).
  • Buff Spiked Mines cost decreased ($12,000 → $10,000)

Version History (BTD6)[]

Initial release (compared to BTD5)
  • Buff Bigger Stacks costs less ($700 → $650).
  • Buff White Hot Spikes costs less ($900 → $800).
  • Nerf Spiked Mines no longer has increased attack speed.
  • Buff Faster Production costs less ($800 → $700).
  • Buff Even Faster Production costs less ($1,250 → $900).
  • Nerf MOAB SHREDR (old MOAB-SHREDR Spikes) no longer has increased attack speed.
  • Buff Spike Storm costs less ($6,500 → $6,000).
  • Nerf Spike Storm now has an initial cooldown before initial use.
  • Nerf Spike Factory will not dispense spikes if not in range of any track, rather than dispense spikes randomly around itself. Nerf due to MOAB-Class Bloons large hitbox.

Balance Changes[]

  • Nerf Permaspike price increased ($22,000 → $25,000).
  • Nerf Permaspike produces spikes 66% slower than normal.
  • Buff Apopalpyse Mode will no longer remove Spike Factory spikes until the time limit is reached.
  • Change Spike Factory spikes will fade away as their lifespan ends rather than disappearing out of existence.
  • Change Spike Factories can no longer throw spikes further outside of the track than the actual bloon exit point is.
  • Buff Super Mines attack speed increased by 20%.
  • Buff Spiked Balls price reduced ($2,400 → $2,200).
  • Buff Spiked Mines price reduced ($14,000 → $12,000).
  • Buff Super Mines can now pop all bloon types.
  • Buff Super Mines pierce increased (40 → 60).
  • Buff MOAB SHREDR price reduced ($3,000 → $2,500).
  • Buff Spike Storm price reduced ($6,000 → $5,000).
  • Buff Carpet of Spikes price reduced ($50,000 → $42,000).
  • Buff Spike Storm and Carpet of Spikes abilities now deals +1 damage to MOAB-class (as intended).
  • Buff Carpet of Spikes +1 damage to all attacks is now applying correctly to the ability and periodic storm for a total of 2 damage to regular bloons and 5 damage to MOABs.
  • Buff Spiked Balls now deals more damage to Ceramics (3 → 4; essentially +3 damage compared to against normal bloons).
  • Buff Spiked Mines explosion damage increased (4 → 5).
  • Buff MOAB SHREDR damage to MOAB-class increased (4 → 5).
  • Buff Carpet of Spikes damage to MOAB-class increased (5 → 6).
  • Buff Permaspike with Bigger Stacks now has larger stacks (60 → 70; effectively now up to 800 damage per spike pile for Permaspike with Bigger Stacks).
  • Buff Super Mines base spike damage increased (1 → 10).
  • Buff Super Mines attack speed increased by 20%.
  • Buff Spike Storm ability now (correctly) has +1 MOAB-class damage from an earlier MOAB-SHREDR blimp damage buff.
  • Buff Spiked Mines explosion damage increased (5 → 10).
  • Buff Super Mines explosion damage increased (350 → 1,000).
  • Nerf Perma-Spike duration decreased (350s → 300s).
  • Nerf Perma-Spike price increased from ($25,000 → $30,000).
  • Nerf Perma Spike max rounds reduced (4 → 3).
  • Change "Directed Spikes" renamed to "Smart Spikes".
  • Buff Smart Spikes attack rate increased by x4 for the first 2.5 seconds of each round.
  • Buff 3-x-x Spiked Balls damage increased (1 → 2).
Bigger balance shifts including Super Mines were not feasible for this update, but we did make a meaningful price reduction.
~ Ninja Kiwi
  • Buff 5-x-x Super Mines Price reduced ($175,000 → $162,500).
  • Buff x-5-x Carpet of Spikes now correctly gains +2 damage to all, not just 1.
Since launch xx2 has never brought enough to the table as a crosspath. Working into the long life trend of the bottom path we felt that introducing longer life at a 'cross-pathable stage' may work in some new niche. Along with this we made a couple small tweaks buffing what should be the 'strength areas' of a few of the more underperforming high tier Spike upgrades.
~ Ninja Kiwi
  • Buff 4-x-x Spiked Mines blast radius increased (15 → 19).
  • Buff x-x-1 Long Reach lifespan increased (70 → 100).
    • 041 Spike Storm lifespan will increase by 50% with this change.
  • Buff x-x-4 Deadly Spikes last for 1 more round before expiring.
  • Bottom Path upgrade changes do not affect Long Life Spikes or Perma-Spike.
  • Buff x-5-x Carpet of Spikes passive cooldown reduced (20s → 15).
  • Change Descriptions changed.
We quite liked how the lifespan changes for xx1 spikes went previously, though this still wasn't enough to make the path competitive and increasing this number further wouldn't have much of an impact since most earlier rounds aren't long enough. Spiked Balls strats have also felt too strong compared to higher tiers on top path, so touching on all of these issues slightly the base lifespan of spikes has been reduced, ceramic bonus increased on 4xx, and a new bonus added to 5xx. We have also made changes to give more purpose to 042 Spike Storm and allowed x5x Carpet of Spikes to save its cooldown so it is no longer required to avoid saving to be used in reliable strategies.
~ Ninja Kiwi
  • Nerf Base spike lifespan reduced (70s → 50s).
    • x-x-1 spike lifespan remains at 100s.
  • Nerf 1-x-x Bigger Stacks cost increased ($600 → $800).
  • Buff 2-x-x Red Hot Spikes cost reduced ($800 → $600).
  • Buff 4-x-x Spiked Mines ceramic damaged increased (+3 → +6).
  • Buff 5-x-x Super Mines spikes now trigger a smaller explosion of radius 20, pierce 10 and damage 10.
  • Buff 0-4-2 Spike Storm targets only active paths.
  • Buff x-5-x Carpet of Spikes saves cooldown of passive ability when saving.
Like a few other towers before it, the attack speed crosspath for Spike Factory has outshined the others. We have reworked the lower Spike Factory tiers to distribute this power more evenly while keeping high tier factories at a similar level of power.
~ Ninja Kiwi
  • Nerf Base Spike Factory cost increased ($800 → $1,000).
  • Buff Faster Production cost decreased ($700 → $600).
  • Buff Even Faster Production cost decreased ($900 → $800).
  • Buff Spike Factory base attack rate increased (2.2s → 1.75s).
  • Nerf Spike Factory attack speed bonus decreased (0.6x → 0.8x, or +66% → +25%), for less attack speed (1.32s → 1.4s).
  • Buff Spike Factory attack speed bonus increased (0.75x → 0.70x, or +33% → +42%), for more attack speed (0.99s → 0.98s).
  • Buff Carpet of Spikes price reduced ($42,000 → $40,000).
  • Buff [undocumented] Base Super Mines attack speed increased (4.4s → 3.5s).
  • Nerf [undocumented] 5-1-0 Super Mines attack speed decreased (2.64s → 2.8s).
  • Buff [undocumented] 5-2-0 Super Mines attack speed increased (1.98s → 1.96s).
  • Nerf [undocumented] 0-1-5 Perma-Spike attack speed decreased (3.6s → 4.8s).
  • Nerf [undocumented] 0-2-5 Perma-Spike attack speed decreased (2.7s → 3.36s).
Spiked Balls are used quite a lot, but we like their overall position right now so they have had only a slight bump up in price, along with a bigger decrease to the price of T4 Spiked Mines. In addition, Permaspike's neglected crosspath has had a small pierce increase as currently their only real use is under custom challenge rules.
~ Ninja Kiwi
  • Nerf 3-x-x Spiked Balls price increased ($2,200 → 2,300).
  • Buff 4-x-x Spiked Mines price reduced ($12,000 → 11,000).
  • Buff 1-0-5 Permaspike pierce increased (70 → 80).
  • Change [undocumented] "Smart" targeting priority now places spikes as far back on the track as it can rather than as far forward to the first bloon.
Pierce amounts for Spiked Balls and Mines fits their use cases too awkwardly due to super ceramics. Considering the power of Spiked Balls, their pierce has been reduced slightly to add value to the pierce focussed higher tier in addition to a price cut for Spiked Mines.
~ Ninja Kiwi
  • Nerf Spiked Balls pierce reduced from 17 to 14. Also affects later upgrades.
  • Buff Spiked Mines price reduced from $11,000 to $9,500.

Bug Fixes and General Changes[]

  • x-5-x Carpet of Spikes passive storm no longer counts as an 'ability cast' for co-op summary.
  • x-4-0 Spike Storm no longer gains a pointless targeting option.
    • x-x-1 Long Range description changed from "Increases range over which spikes can be deposited." to "Increases range for spike pile drops, plus piles last longer." to reflect buffs.
    • x-x-4 Deadly Spikes description changed from "Extra deadly spikes can pop through 2 layers per spike." to "Extra deadly spikes can pop through 2 layers per spike and last another round." to reflect buffs.
    • x-x-5 Perma-Spike description changed from "Spikes become almost permanent." to "High damage spikes become almost permanent."
      • All of the description changes were not directly documented in the Patch Notes.
  • Buff 0-4-2 Spike Storm now correctly works on splitting tracks.


Main article: Spike Factory/Strategies


Spike Factories are tailor made for guarding exits but can be used anywhere. Powerful upgrades include: White Hot Spikes, Spiked Ball Factory, MOAB-SHREDR, Spike Storm.
~ BMC Flash description
Generates piles of road spikes around the track automatically. Leftover spikes disappear at the end of each round.
~ Bloons TD 4 Description
Generates piles of road spikes on bits of nearby track. Each pile can pop 5 bloons, and unused spikes disappear at end of each round.
~ Bloons TD 5 Description







The Spike Factory is out!

  • In BTD4, sometimes the Spike Storm will only cover 1/4-1/2 of the track, while in BTD5, it covers the whole track, but the spikes disappear faster than in BTD4.
    • However, there was originally a bug where the Spike Storm ability only placed spikes in the Spike Factory's range.
  • The spikes created by the Spike Factory will not be placed on the track if the Spike Factory placed far enough from the track. However, in BTD5 the spikes still have an effect if bloons hit it when being blown back by upgrades such as Distraction.
  • Some players tend to call this tower the "Spactory", which is an abbreviated and shortened version of "Spike Factory".

Specific to BTD4[]

  • This tower has the same colors as the Dartling Gun in BTD4. Both start out green/yellow at levels 1-3, blue/purple at level 4 and red at level 5.
  • There is no hotkey for the Spike Factory in BTD4.
  • In BTD4, each pile (without upgrades) appears to have 6 spikes, but it will pop only 5 bloons.
  • In BTD4 iOS, there is a glitch that the Spike Factory can produce bigger stacks even without any upgrades.
  • In BTD4 Expansion, the Spike Factory's logo in the shop is a Dart Monkey along with the Dartling Gun.
  • In BTD4, Spike Factories may not place spikes in the track if placed too close to the Bloons' path.

Specific to BTD5[]

  • It is possible to beat the entire game with only this tower because it can pop Camo Bloons, and with White Hot Spikes, Lead Bloons.
    • This can be made even easier on the mobile version with the maxed specialty building.
    • In BTD5, the player only needs 2 of these to beat Monkey Lane on Easy (even without selling them or using Road Spikes), and having both of them be 4/1 or 4/2 or with Tack Awesomizer is optional.
  • In Bloons TD Battles, after the release of Bloontonium Mine, the Spike Factory was nerfed to fire half as fast compared to BTD5 and BMC with the spikes popping twice as many bloons as before.
  • In BTD5, there is a glitch where when you buy Even Faster Production, it doesn't load the upgraded look unless it is under the range of a monkey village.
  • In BTD5 (not Mobile), the piles with the Bigger Stacks upgrade won't pop the same amount as regular Road Spikes (10 and 11 Bloons respectively).

What remains of a BFB when spikes are placed close to the entrance, but not close enough to pop the regular bloons

  • On certain maps where the exit is parallel to the start, spikes that are placed at the exit will only pop MOAB class bloons because of their size. This is a great way to pop the MOAB layer, especially in Bloons Monkey City where many maps are like this.
  • A 2-2 Spike Factory in earlier versions of BTD5 Flash used to look the same as an 1/1 one if upgraded to 1/1, then both tier 2 upgrades were bought. This could be solved by placing a village near the Spike Factory.
  • The Spike Factory is the only tower other than the Boomerang Thrower that has different price in BMC than in BTD5. In BTD5 Mobile however, Boomerang Throwers cost $400.
  • In Bloons TD Battles, Spiked Mines were a great way to freeze the opponent's computer, when spammed, due to the extreme amount of explosions.
  • Upgrading a Spike Factory in both paths gives it a unique appearance, somewhat blending the colors of both upgrades.
    • Upgrading a Spike Factory from 4/0 to 4/2 will turn it orange instead of the usual red, and upgrading a Spike Factory from 0/4 to 2/4 will turn it green instead of the usual blue.

      1/1 and 2/1,1/2,2/2 spike factory in BTD5

      A 2/3,2/4 and 4/2 spike factory

  • In Bloons Monkey City, the claim of the strength that it "never misses" is not entirely true, because if a Pink Bloon zooms fast enough past the Spike Factory, it cannot spew out the piles fast enough to catch it, unless it is placed far enough from the entrance.
  • In Bloons Monkey City, the range of the Spike Factory is the range it had when placed. This means that when you place a Spike Factory and then a Monkey Village upgraded 1/0, it will only produce spikes inside the original range. If you place the Monkey Village first, the range will be increased.
  • In BMC, 3 4/2 Spike Factories can beat any tiles with only one ending.
  • They are restricted on Desert and High Desert BMC tiles.
  • After a round in BMC, its spikes will disappear, with the exception of an MvM attack, where they will only disappear if they stay too long on the track or are used up.

Specific to BTD6[]

  • The Spike Factory can have problems with extremely fast bloons such as freeplay DDT's in BTD6 (about Round 200+). If Bloons go fast enough it is possible for them to pass over the spikes but not register hitting them causing the bloons to take no damage.
    • This happens because in one frame the bloon is behind the spike pile, and in the next frame the bloon is in front of the spike pile. It essentially teleported over the spike pile.
  • In BTD6, the Spike Factory spikes in Apopalypse automatically disappeared once a round ends, which rendered the Spike Factory much less powerful due to disappearing at the wrong time. This has been fixed, changing the spikes to last between rounds, like in BTD5.