Enemies and combat

This planet that you have crash landed on already has a native species inhabiting it, and as you will soon find out they are not very happy with your arrival…

There are three different types of enemies in the game. Two of them are mobile creatures and the third is stationary but quite powerful. There are also multiple levels or stages of each type of enemy unit. The two mobile creatures are called Biters and Spitters. They are bug like creatures, with the Biters being similar to something like a cockroach or beetle and the Spitters being like worms. The third type of enemy is actually a Worm that can't move but has a large range and packs a really big punch even in later stages of the game. There are four different levels of Biters and Spitters, and three levels of Worms. It is important to note that Biters do physical damage and Spitters do acid damage. This is good to remember because it plays a factor when attacking them or being attacked by them. Below is a list of each one with a little info about it.

Biters: The Biters are the first enemies you will see in a new game since they spawn before Spitters. They are fairly quick, being able to chase down a player most the time. However the Small Bitters can be held off by the player with relative ease since they are quite weak. The Medium Biters will pose a problem though because they have more health and some resistances. The Big and Behemoth Biters will be the real challenge as they are nearly immune to regular gun fire/physical damage and pack a huge punch.

Small Biters: Weakest type of Biter and can easily be killed with any type of weapon. There will only be Small Biters in the beginning of the game.

Medium Biters: Slower than Small Biters but also stronger. Have a higher attack and more health and resistance. Have 10% explosion resistance, and 4 flat physical resistance. Resistances will be explained a bit later in this section.

Big Biters: Very strong both with it's resistances and damage. They have 5x the health of Medium Biters, do twice as much damage and have double the physical resistance (so 8 flat resistance). Because of their high physical resistance they are nearly immune to regular gun fire with anything that does physical damage. They can also attack through walls and hit objects directly behind the wall.

Behemoth Biters: The last stage of Biters are by far the most powerful. They are extremely dangerous and are very, very durable. They have more than 13x the amount of health of a Big Biter, and do more than 3x the damage. They also have an explosion resistance of 10/20%, so 10 flat and 20% reduction. As well as physical resistance of 8/20%. Can attack through walls and hit objects right behind the walls just like the Big Biters.

Spitters: The Spitters are similar to Biters in their behavior and have the same four sizes, but do have a few key differences. The first is that they attack at range, and shoot an acid projectile that can't be dodged and will deal damage the target at which it was shot. They also do acid damage rather than physical damage. This is important because the acid resistance of buildings and armor is usually much less than the physical resistance so the Spitters will do more damage than the Biters.

Small Spitters: Weakest of the Spitters and very squishy so they are easy to kill. They do attack at range though and do a fair bit of damage since it is acid damage.

Medium Spitters: Slower than the previous Spitters but also more dangerous. Have 5x the health of a Small Spitter and do 2x the damage. Also have an explosion resistance of 10%.

Big Spitters: Has 4x the health of a Medium Spitter so can take a lot more damage. Does more damage as well and has an explosion resistance of 30%.

Behemoth Spitters: Even bulkier than the Big Spitters. Have 10x the health of a Big Spitter and do almost 2x the damage. Have an explosion resistance of 35%.

Worms: The Worms are the static defenses of the Biters/Spitters and act like turrets. While they cannot move they do have a large range and deal quite a lot of damage even at their smallest stage. Their inability to move does make them vulnerable to certain attacks which will be covered later in this section. They also deal acid damage like the Spitters. The Worms come in three different sizes similar to the other two enemies. Unlike the Biters or Spitters, the Worms size is not influenced by pollution or game progression. Even medium and big Worms can spawn at the beginning of the game, and sometimes are on their own and not with any spawners.

Small Worms: The weakest of the three Worms but still not easy to kill. Has 200 health, which for comparison is the same as a Big Spitter or about 2.5x that of a Medium Biter. They do the same amount of damage as a Small Spitter.

Medium Worms:Medium Worms: The Medium Worms are quite dangerous and can pose a problem even for more experienced players. They have more health than the Small Worms, do 3x the damage and have 5/15% explosion resistance, and 4 flat physical resistance. They should be approached and handled with caution.

Big Worms: The most powerful of the worms and by far the most durable. They deal twice the damage of a Medium Worm and have 500 health which for comparison is 150 more than a Big Biter. They also have 10/30% explosion resistance, and 8 flat physical resistance so they are pretty much immune to any normal gunfire or even grenades. Have a long range so you can't get close enough to shoot them yourself without taking fire from them.

If you would like some more detailed info on the enemies, such as their exact health and such then you can check out the Factorio wiki page.

One of the last bits to cover before we move on to the actual combat part of this section is how the enemies interact with the pollution produced from your factory. Probably the most important part of this is that your pollution is actually part of what effects the Biters and Spitters evolution. As the enemies evolve, the larger sizes/levels of them start spawning. The pollution also attracts and, in fact, enrages the Biters/Spitters which is what makes them attack your base. As soon as pollution starts to hit a Spawner the Biters/Spitters will start attacking fairly shortly afterward.

They will seek to destroy the source of the pollution but will switch targets if something of higher priority gets in the way such as the player or static defenses like walls or turrets. They are also able to navigate around obstacles to some degree in order to find holes in the defenses.


The resistances in Factorio are actually pretty simple. They are calculated by reducing the incoming damage by the percentage first if there is one, and then by the flat amount. So to better explain this lets use the Behemoth Biters as an example. If you remember, they have a physical damage resistance of 8/20%. Let’s say you have a weapon/ammo that does 12 physical per shot. When you shoot the Behemoth Biters, that 12 damage would be reduced by 20% first, so you would only do 80% damage which would be 9.6 damage. At this point the flat amount is taken into account. So for this they have a flat resistance of 8, which means you would then do 1.6 damage per shot. It works this way for anything with a resistance such as buildings, vehicles or armor etc.


The enemy evolution in Factorio is determined by and increased by three factors. These are the passing of time, pollution, and destruction of enemy spawners. As time passes it slightly increases the evolution factor. The production of the pollution increases it a bit more than the passing of time, and then destroying spawners increases it significantly.


I'm sure after reading the info about the enemies in the above section you might feel pretty worried about how you will handle them. Honestly, it would be quite difficult if you had no knowledge beforehand about how to deal with them, but that is what this guide is for, to help you get a better grasp on things beforehand. Luckily there are a lot of different weapons and devices you can use to face off against the enemies. I will not go over what every single thing does in this section because that would take forever.

If you don't know what something does, take a look in the Item Index section and each item will have a short description.

In my opinion there are three different stages of combat in Factorio. Early game combat, mid game combat, and late game combat. The reason these are different is because of the evolution factor of the enemies at each stage is different, and so is the equipment that you can use to fight them. We will start with going over some ways to defend your base against attacks; however I won't go into this too much because it is pretty easy to figure out on your own (essentially just walls and turrets). After that we will move on to the offensive part of the combat which I think is one of the most fun parts of the game and is when you really get to utilize the cool weapons and equipment.


Defending against the Biters/Spitters will be an important task (unless you're playing on peaceful mode) because otherwise they will just come and destroy your whole factory. There are essentially two ways to defend yourself and your base, and those are static defenses (walls and turrets), and then the other is the weapon you carry. While you can fend them off for a little bit with just your personal weapon you will need some static defenses shortly after you start getting attacked.

At first you will be best off just placing turrets around your factory in the key spots that the enemies seem to attack. Once you get the ability to make walls and have some decent production of ammo and turrets then there are two main ways to set up static defenses. You can wall off your entire base with turrets behind the wall:

You can also set up little defense outposts around the edges of your base:

Obviously walling off your whole base is more time consuming and costly but the advantage is that you know there aren't any holes or blind spots in the defenses. Going the outpost route is cheaper and faster and if done right can be quite effective, but still leaves potential holes in your defenses. The choice is yours and really based on the situation and your personal preference.

The turrets in Factorio are very strong, so the Gun Turrets will do great against Small Bitters/ Spitters, and even fairly well against Medium Biters/Spitters. You can also increase the effectiveness of them with turret and bullet damage technology upgrades, as well as using Piercing Ammo. However, once a lot of Medium guys start spawning and especially when Big guys start spawning, you will need to make the switch to Laser Turrets otherwise you will get overrun. Even without upgrades the Laser Turrets are extremely powerful, being able to cut through Medium Biters/Spitters like butter, and even doing quite well against Big guys unless there is a large group of them.

If you really want to get crazy with your defenses you can use belts to your advantage. If you place them on the outside of the wall either running away from the wall or towards the wall you can push or pull the enemies where you want them. Having the belts running away from the wall is great against Biters because it makes it quite difficult for them to actually reach the wall and attack it since they are constantly being pushed away. Here is what that belt setup might look like:

If you have the belts running towards the wall that can be effective against Spitters because it will pull them more into range of the turrets so they will die easier and potentially not do as much damage. That would just look the opposite of the example this example.


There are essentially four reasons why you would need to go on the offensive and actually attack the enemies and their bases. Either they are too close to your base and just causing too many problems with constant attacks, they are in the way of a mining outpost or train track etc, or you need to acquire Alien Artifacts to make your Purple Science Packs. The fourth reason is you just feel like going out and killing aliens for fun…

Early Game Combat
Regardless of the reason, you have multiple tools and methods at your disposal to bring the fight to them. In the early game before you get Tanks or Poison Capsules or Combat Robots, the main way to take out Spawners and the enemies surrounding them is either with your personal weapon/armor and careful maneuvering, or using the turret creep method. The turret creep is by the far the most effective and even stays quite effective far into the late game if you do it right. Turret creep is essentially like playing leapfrog with turrets. You place some down, then move forward a bit and place more down, and then pull up the ones from behind and move those forward, etc.

Here is a video that demonstrates it as well. The video is actually about mid game combat and features the tank, but the turret creep is featured in it as well:

If you have enough turrets and ammo (if you’re using gun turrets) and do it carefully then you can take out almost any sized base using this method. Here is another video that goes over really early game combat using just your personal gun and some smart maneuvering.

Mid Game Combat
At this point there will probably be Medium Biters/Spitters spawning and possibly even a few big ones depending on how much the evolution factor increased. But once you get into mid game combat there are quite a few different ways you can attack the Biters. Again, the turret creep method is still quite effective especially because at this point you will probably have Laser Turrets. You also will have access to the Tank as well as Poison and Slowdown Capsules, and maybe some Defender Capsules.

The Tank is a great way to take out Spawners at this stage of the game. It can take out a Spawner in two shots, and do about the same to Worms. It’s long range cannon allows you to hit the Spawners or Worms at range while kiting the Biters/Spitters around behind you.

Tanks also have very high health and resistances so they are quite sturdy and can take a lot of hits. Since they have a very high impact resistance you can actually kill things like Spawners, some Worms or even trees by simply running straight into them with enough forward momentum (picture below):

The Tank cannon is very powerful against structures and can be against enemies if you are a good enough aim to hit them. Luckily the Tank has a machine gun on it as well for close combat against Biters/Spitters, which you can switch to like normal by using Q. You can stick normal or Piercing Ammo in it as well.

Poison Capsules are one of thebest ways to kill Worms without actually taking any damage from them if you do it carefully. The range from which you can throw the capsule actually barely out-ranges even the Big Worms so you can hit them and never take damage if you're careful. Poison Capsules obviously do poison damage and it does continual damage per-second. The effects can also stack, so throwing five of them on the worm will kill it even faster.

They do damage Biters and Spitters as well, but they do not damage Spawners.

If you want a video demonstration, the video featuring turret creep that is linked in the Early Game Combat section shows usage of the Tank too, as well as Poison Capsules and Distractor Capsules.

Fire system
The new fire system in 0.13 allows for a level of automated environmental destruction previously impossible. Watch as entire forests ignite and burn with flames, as the local inhabitants succumb to the heat. The new fire damages all around it, and spreads itself among trees. This powerful new system is very effective for clearing out large areas of enemies.

The handheld flamthrower and flamethrower turret both shoot a stream of burning fluid toward the enemy, which combusts into a blazing wall when it hits the ground. Any enemies caught in it will catch on fire and take large amounts of damage, any trees near the fire will also start to burn. There is no way to stop the fire, except for cutting down any trees in its path. Burning trees can release huge amounts of pollution, so be careful not to overdo it, or you might be the one feeling the heat.

Late Game Combat
In my opinion the fighting in the late game is when the real fun begins. At this point the Tank actually starts to lose effectiveness due to the increase in numbers of Biters/Spitters than earlier in the game. If you get surrounded, you will be killed by all the Big and Behemoth enemies. In the late game you should have access to Power Armor and Distractor/Destroyer Capsules. The Distractors could technically be used in the mid game but they are fairly expensive to make and you need a lot of them to be effective so usually you won't have enough of them until later.

In addition to the things listed above you will also have access to the Combat Shotgun and Piercing Ammo for it and hopefully a few shooting speed and damage upgrades for it. You can combine all these tools and equipment together to pretty much make yourself a walking war machine. The Power Armor (especially the MK2) has multiple slots in it that you can put Shields and Exoskeletons in to enhance it's ability and in turn your abilities. There is also a Personal Laser Defense that you can put in but it is pretty ineffective for the most part.

You will need some Fusion Reactors to actually power the things that will go in your suit. There are many different ways to set up your armor but you need to make sure you have enough power to run everything otherwise you will have problems such as your Exoskeletons turning off while the shields try to recharge. It is best to have enough Exoskeletons to be able to outrun the enemies so they can't surround you or chase you down. Since we are talking about late game here I will use the MK2 Power Armor for an example. You can configure the suit however you see fit and works best for you, but one of the more popular setups includes 3 Fusion Reactors, 4 Exoskeletons, and 5 Shields, or 2 Reactors, 6 Exos, and 4 Shields.

To open your Power Armor, just Right-Click on it when it is in your armor slot. You can then just add things to it by dragging and dropping them, and take things out by either Right-Clicking or dragging and dropping them out.

Using a good Power Armor setup, a Combat Shotgun with Piercing Ammo, and some Destroyer Capsules you can rain destruction down on almost everything. You can also throw down some Distractor Capsules as well to make the process even more effective. Remember though that the Distractors are stationary whereas the Destroyers follow you around. If you use Distractors it is best to try and throw them right on top of the Spawners because it makes it harder for the Biters to hit them and that way you know they will be able to shoot the Spawner.

So to summarize, the basic strategy for taking on enemy bases in the later stages of the game is to have a good Power Armor setup, throw out some Destroyer Capsules to follow you around, and then just make sure to kite the Biters/Spitters around so you don't get surrounded. Make sure you are in range for your Shotgun to reach the Spawners and Worms because it will just rip through them. If there are Worms, especially Big Worms, make sure to target those down near the beginning otherwise you will take a lot of damage from them. Your Destroyer Capsules will help kill the enemies that are following you, and if they have a chance they will help shoot down the Spawners and Worms as well.