Spikes become almost permanent.
~ Upgrade description in BTD6.

Perma-Spike (sometimes referred to as Permaspike) is the final upgrade of Path 3 for the Spike Factory in BTD6. The spikes produced by the Spike Factory pop 50 bloons per pile (70 bloons with Bigger Stacks) but deal 10 layers of damage per spike for a total of 500 damage per spike pile (700 with Bigger Stacks), making it extremely powerful for stockpiling spikes. Despite the name, but in accordance with the upgrade's description, the spikes are not actually permanent. The spikes last between rounds and have a longevity of 3 rounds each or 300 seconds, whichever comes first.

It costs $25,500 on Easy, $30,000 on Medium, $32,400 on Hard, and $36,000 on Impoppable.


  • Always purchase this upgrade on single-entry or single-exit maps near the end of the track. Then, spikes won't be used up immediately, allowing spike stockpiling to slowly make the tower more and more valuable. Even though this may make the Perma-Spike less useful evidently, it is still the best way to use it.
  • It is recommended to purchase the Path 2 Upgrades (Faster Production and Even Faster Production) over the Path 1 Upgrades (Bigger Stacks and White Hot Spikes) as Bigger Stacks only increases its pop count per spike from 500 to 700 and, although White Hot Spikes allows it to pop any D.D.Ts that may rush through a defense, a Monkey Intelligence Bureau or Acidic Mixture Dip can easily solve that problem while also providing it and other nearby towers with the bonus as well.
    • Path 2 upgrades will add 122% extra pops with a fast refresh, while Path 1 upgrades will add only 40% extra pops with a slow refresh but allows Lead-popping. It is worth noting these two facts.
    • Where Alchemists are available, it is best to purchase a 0-2-5 Perma-Spike nearby a 2-0-0 Alchemist at minimum, preferably a 3-0-2 (or 4-0-2) Alchemist for extra damage, pierce, and attack speed (and range, but that's irrelevant to DPS). When using an Alchemist in place of Monkey Intelligence Bureau, the Perma-Spike should be the only tower in range of the Alchemist.
  • Overclock works exceptionally well with Perma-Spike even when paired with Stronger Stimulant. In fact, it is still slow enough not to consume Alchemist buffs faster than can be re-supplied.
  • Ultraboost and Perma-Spike are a great combo, maxing out the Ultraboost on the Perma-Spike permanetly makes the Perma-Spike shoot 2x fast! This can be another way to make sure just incase the bloons or MOABS or the B.A.D get past. 
  • Note that leaving the game and re-entering will no longer erase the spike piles as of Version 12.0. Interestingly, Long Life Spikes and Deadly Spikes spike piles can be erased.
  • Be cautious of using Snowstorm, as Perma-Spike without White Hot Spikes (or using an MIB) cannot affect frozen MOABs, allowing them to cross Perma-Spike undamaged, especially if using 'smart' targeting, where all spikes end up in one pile. Note that Acidic Mixture Dip cannot grant frozen-popping, despite granting lead-popping.
  • Due to the nature that occasional server reconnections may be caused by the extreme lag on the device, even if the spike piles can be saved, it is better off not using Perma-Spike for Co-Op Mode.


Perma-Spike is one of the most cost-efficient forms of exit protection for almost all stages of the game. Despite Perma-Spike's slow attack speed, its super sharp spike piles will pack a huge punch to bloons that approach them if used correctly. At the cost of one-third of the original attack speed, each spike deals 10 damage with up to 50 spikes per pile and last for a significantly long time. Due to the superior long-term benefits of stockpiling spike piles, it is better off using Perma-Spike as exit protection rather than as an offensive tower.

Perma-Spike increases much of its potential via the use of stat boosts, especially those that increase attack speed. Crosspathing to 0-2-5 Perma-Spike, which increases attack speed by 122%, will effectively grant 2.2x more damage stockpiling than a non-crosspathed Perma-Spike. On the other hand, a 2-0-5 Perma-Spike grants only +20 pierce, which effectively only adds 1.6x more damage stockpiling at a slower refresh rate. Thus, it is better off crosspathing the Spike Factory with Path 2 prior to getting Perma-Spike.

In addition to internal upgrade boosts, Perma-Spike benefits greatly with external sources of stat boosts; this makes it a good combo with a 2-x-x Jungle Drums Village and a 3-0-2 Berserker Brew Alchemist (or 4-0-2 Stronger Stimulant Alchemist for slightly better results, though 3-0-2 is generally sufficient). Besides simple attack speed bonuses, the extra damage and pierce add significantly greater damage-stockpiling potential to Perma-Spike. In addition, the slow attack speed of Perma-Spike ensures that the Acidic Mixture Dips do not expire immediately, thus producing "permanent" lead-popping power, rendering the Path 1 Perma-Spike crosspath useless when Alchemists are enabled. However, if Alchemists aren't available, you could always use a Monkey Intelligence Bureau to guarantee lead-popping power for it and all towers nearby.

Overclock can be used to further boost Perma-Spike to further increase the Spike Factory's power. For the price of approximately 40% of the cost of Perma-Spike, itself, it can double the attack speed of Perma-Spike, resulting in an incredibly tough spike stockpile. Overclock usually has up to 100% uptime, so on most occasions it can be reactivated to Perma-Spike consistently without any buff downtime. Even with Stronger Stimulant, an Overclocked Perma-Spike with nearby Jungle Drums would still be slow enough not to consume Alchemist buffs (especially Acidic Mixture Dip) faster than can be re-supplied. The only downside to Overclock is that a non-discounted 0-2-5 Spike Factory currently costs $40,870 on Hard Mode, which barely passes the $40,000 full-duration overclocking limit, which means it can only be overclocked up to 2/3 of the time without adding a second Overclock to reset the old expired one. However, this pricetag limitation could be overcome by placing double Monkey Commerce discounts for the 0-2-3 Spike Factory prior to Perma-Spike, including the base cost of the Spike Factory, thereby reducing the total cost of the Perma-Spike down to just less than $40,000.

Other methods of optimizing Perma-Spike include stalling out the rounds so that it can produce many more spikes per round in preparation for future rounds. Maim MOAB set to Last and targeting on ZOMGs will ensure that they will be stunned so that none of the towers except a single Maim MOAB can attack the ZOMG, thereby giving Perma-Spike more time to stockpile extra spikes. 0-x-2 Ice Monkeys stalling Super Ceramics are another viable method of stalling out rounds.

Optimal Perma-Spike spots are important to consider prior to placing Perma-Spike. Important aspects to consider include whether Perma-Spike is far enough from the map to provide maximum stockpiling potential, whether the spikes avoid any potential to accidentally become consumed by incoming entrance bloons, whether sufficient exit-stopping coverage is achieved, and, in the case of multiple paths, whether all paths are covered by the spikes. All of these aspects determine how "good" of a placement a Perma-Spike is. In C.H.I.M.P.S. Mode, it is impossible to resell to re-position the Perma-Spike placement, so be sure to plan placements prior to placement.

There are only a few maps where the Permaspike may have a few complications when it comes to optimization, which comes due to the lack of single-entry-single-exit on certain maps. Usually setting the target to Close should help target out the intersections of exits. However, there is no easy solution to optimizing Permaspike on harder maps such as #Ouch or Muddy Puddles, where there are either multiple intersection exit points or multiple disconnected exits. To solve the latter problem, Support Chinook could be used to carry Permaspike along the map each round to organize into their new appropriate exit-protection roles. Unfortunately, Permaspike may have trouble on Quad, due to the map having multiple non-converging lanes that do simultaneously allow bloons to enter and/or exit; as a result, it will be very difficult to maintain good Permaspike piles on all four intersection points, even with Support Chinook. It is near impossible to provide a good Permaspike spot for the map Bloody Puddles, as there are both two simultaneously occuring paths per round as well as alternation between each of the multiple paths, a combination combining all of the worst map aspects for Permaspike.

Optimal Permaspike PlacementsEdit

(Construction: Will add optimal Spike Factory spots later with a gallery dedicated for Spike Factory spots. Will in addition discuss best use of Permaspike, including best upgrade combinations, best towers to pair nearby, and other good tips with Permaspike.)

Update HistoryEdit


Nerf Perma-Spike price increased ($22000 → $25000).

Nerf Perma-Spike fire rate decreased by 66%.


Buff Permaspike with Bigger Stacks now has larger stacks (60 --> 70; effectively now up to 700 damage per spike pile for Permaspike with Bigger Stacks)

  • Nerf Perma-Spike duration decreased from 350s-> 300s
  • Nerf Perma-Spike price increased from 25k to 30k
  • Nerf Perma Spike max rounds reduced from 4 -> 3
  • Buff Perma-Spike spike piles can now be saved (i.e. on any type of game save, including Co-Op saves)



  • This is one of the few towers that can destroy a B.A.D. singlehandedly if given lead popping power and sufficient time to stack its spikes. The other towers are the Legend of the Night, Ezili with her level 20 ability, the Apache Prime upgraded with the 2nd path, the Sun Temple and True Sun God if given sufficient sacrifices.
  • This has been used by many, if not, all players to beat Dark Castle C.H.I.M.P.S..
  • Between Version 2.0 and 11.2, a 0-2-5 can achieve a spike pile that can store around 65,000 pops worth of spikes if allowed to create a full stack.
  • The description of the upgrade says "Spikes become almost permanent!", however, they only last about 3 rounds or 5 minutes, whichever is sooner.

Start a Discussion Discussions about Perma-Spike

Community content is available under CC-BY-SA unless otherwise noted.