You'll go through a lot of bullets in Once Human, and if you want to keep your guns loaded to stop the endless stream of interdimensional abominations that threaten you, you're going to need to craft a lot of ammo. To do that, you need the ingredients essential to bullet manufacturing, which includes gunpowder. Making gunpowder, however, requires acid--something you'll have to track down in the world until you can make it yourself.
Acid ends up being pretty important, since it's also a major component in making fuel for vehicles, so you're going to want to get good at sourcing it and farming it as early as you can. Here's what you need to know about where to get acid in the early game and how you can make it yourself later on.
The good news is that, in the early game, you can find a lot of acid just lying around. In most of the early locations as you're completing quests, you'll want to also finish the exploration goals for a given location, which includes finding weapons and armor chests and mystical chests in a given area. That'll get you looking around a lot in any area, picking up as much crafting material as possible.
In general, you should loot everything you can, including trash bins and dumpsters, desks and boxes, and anything else that can be opened--use Spacetime to check what can be looted.
Acid tends to drop from Gnawer enemies when you kill them, but you can get it from lots of baddies in the world.
You can also get acid fairly reliably from enemies you'll see a lot of in the early game. The Gnawer in particular, which is the spindly human-like purple monster that will chase you, tends to drop acid when you kill it. You can also sometimes get acid off the Light enemies (those lightbulb bugs) and the Charred Maniac, the zombies with raider helmets. Other enemies drop acid too, so it's good to make sure you're constantly killing and looting a lot of the creatures you come across.
As you loot your way through locations, most of the time you won't end up with crafting components, you'll wind up with junk that can be turned into crafting components. To break down all those random items that'll wind up in your inventory, you'll need a Disassembly Bench, so this should be one of your main priorities in the early game.
The good news is that you can unlock Disassembly almost immediately in the tech tree. However, in order to actually make a Disassembly Bench, you'll need a Furnace that can make Copper Ingots.
You can unlock Disassembly Techniques really early in the game, but a Disassembly Bench still requires a few steps to actually create.
To get yourself up and running to disassemble junk, head to the Memetics menu. Unlock the Disassembly Techniques and Smelting Essentials nodes on the Infrastructure tech tree. You'll also need the Wooden Support node so you can build a foundation and a base in your territory.
Once you've got the right nodes unlocked, gather some copper ore and logs to build yourself a Furnace, and smelt more copper into Copper Ingots. Use those to build a Disassembly Bench. You'll want to frequently dump all your junk for disassembly after every expedition so you don't get too weighed down, and you'll probably want to construct crates to put crafting materials in. Once Human will draw from crates in your territory when you do crafting, so you won't have to worry about a ton of inventory management.
Eventually, you can cut out the middleman of killing enemies and looting junk to get acid and start refining it straight out of the environment. However, it's going to take a bit--you'll need to advance down the tech trees and level up your character so you can stay alive in tougher locations.
You can filter acid out of water in areas where stardust pollution is higher than normal. You can tell when that's the case if you get a message about stardust pollution increasing on your screen, and the air gets darker and full of more floating particles. These places are dangerous, since exposure to stardust will cut down on your maximum health, so be careful when entering these places.
You need to unlock the full chain of water purification upgrades in the Logistics tech tree in order to make an acid farm.
The good news is that you don't need to worry about farming acid until you've significantly leveled up, so you should be better equipped to handle any dangerous locations. In order to get the ability to passively farm acid while doing other things, you'll need access to the Level 5 Memetics tier.
To passively farm acid, you'll need to unlock the full set of water purification upgrades in the Logistics tech tree. These start in Tier 2, with Rainwater Collection Systems. You want to get all the way down to Tier 5 to unlock Reverse Osmosis Purifiers. You'll also need the Brewing Barrels upgrade from Tier 4. And of course, in order to run all these things, you'll need to unlock the Solar Generator in Logistics Tier 3.
Move your territory so that you're near a polluted water source. There are some in the desert areas around Blackfell, for example, and the swamps near Greywater Camp. Once you've got territory near the water, you can start setting up the devices that will farm acid for you.
First, build and power a Water Pump in the polluted water source and connect it to power. Next, make a Reverse Osmosis Purifier and connect it to the Water Pump. That will automatically start to create impure acid from the polluted water.
A source of impure acid gets you halfway there; you need to purify it into Acid that can be used to make gunpowder or fuel. For that, you need a Brewing Barrel. Connect the Brewing Barrel to the Reverse Osmosis Purifier and make sure the impure acid is in the middle portion of the Barrel's menu.
You can make a use a Water Pump and Compact Water Filter to make pure water, which is the first ingredient you need to make acid.
You also need pure water to create acid. You can get some by building a Water Pump in the water and connecting it to a Compact Water Filter, both of which need to be powered. The Compact Water Filter will make pure water, which you can then add to the Brewing Barrel to create acid.
It's not exactly a hands-off method of farming acid, since you'll still need to move the ingredients around between the different filters, but you can dump impure acid and pure water into the Reverse Osmosis Purifier and go out to do other things while the acid is made.
It takes some grinding to get all this together, but once you have a regular source of acid, you can now make gunpowder. You'll still need two other ingredients, though: Sulfur, which you'll have to mine but which is available all over the place, and charcoal, which you can get by putting any logs in your Furnace.
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Acid ends up being pretty important, since it's also a major component in making fuel for vehicles, so you're going to want to get good at sourcing it and farming it as early as you can. Here's what you need to know about where to get acid in the early game and how you can make it yourself later on.
Where To Get Acid Early
The good news is that, in the early game, you can find a lot of acid just lying around. In most of the early locations as you're completing quests, you'll want to also finish the exploration goals for a given location, which includes finding weapons and armor chests and mystical chests in a given area. That'll get you looking around a lot in any area, picking up as much crafting material as possible.
In general, you should loot everything you can, including trash bins and dumpsters, desks and boxes, and anything else that can be opened--use Spacetime to check what can be looted.
Acid tends to drop from Gnawer enemies when you kill them, but you can get it from lots of baddies in the world.
You can also get acid fairly reliably from enemies you'll see a lot of in the early game. The Gnawer in particular, which is the spindly human-like purple monster that will chase you, tends to drop acid when you kill it. You can also sometimes get acid off the Light enemies (those lightbulb bugs) and the Charred Maniac, the zombies with raider helmets. Other enemies drop acid too, so it's good to make sure you're constantly killing and looting a lot of the creatures you come across.
Make A Disassembly Bench
As you loot your way through locations, most of the time you won't end up with crafting components, you'll wind up with junk that can be turned into crafting components. To break down all those random items that'll wind up in your inventory, you'll need a Disassembly Bench, so this should be one of your main priorities in the early game.
The good news is that you can unlock Disassembly almost immediately in the tech tree. However, in order to actually make a Disassembly Bench, you'll need a Furnace that can make Copper Ingots.
You can unlock Disassembly Techniques really early in the game, but a Disassembly Bench still requires a few steps to actually create.
To get yourself up and running to disassemble junk, head to the Memetics menu. Unlock the Disassembly Techniques and Smelting Essentials nodes on the Infrastructure tech tree. You'll also need the Wooden Support node so you can build a foundation and a base in your territory.
Once you've got the right nodes unlocked, gather some copper ore and logs to build yourself a Furnace, and smelt more copper into Copper Ingots. Use those to build a Disassembly Bench. You'll want to frequently dump all your junk for disassembly after every expedition so you don't get too weighed down, and you'll probably want to construct crates to put crafting materials in. Once Human will draw from crates in your territory when you do crafting, so you won't have to worry about a ton of inventory management.
How To Farm Acid
Eventually, you can cut out the middleman of killing enemies and looting junk to get acid and start refining it straight out of the environment. However, it's going to take a bit--you'll need to advance down the tech trees and level up your character so you can stay alive in tougher locations.
You can filter acid out of water in areas where stardust pollution is higher than normal. You can tell when that's the case if you get a message about stardust pollution increasing on your screen, and the air gets darker and full of more floating particles. These places are dangerous, since exposure to stardust will cut down on your maximum health, so be careful when entering these places.
You need to unlock the full chain of water purification upgrades in the Logistics tech tree in order to make an acid farm.
The good news is that you don't need to worry about farming acid until you've significantly leveled up, so you should be better equipped to handle any dangerous locations. In order to get the ability to passively farm acid while doing other things, you'll need access to the Level 5 Memetics tier.
To passively farm acid, you'll need to unlock the full set of water purification upgrades in the Logistics tech tree. These start in Tier 2, with Rainwater Collection Systems. You want to get all the way down to Tier 5 to unlock Reverse Osmosis Purifiers. You'll also need the Brewing Barrels upgrade from Tier 4. And of course, in order to run all these things, you'll need to unlock the Solar Generator in Logistics Tier 3.
How To Make A (Mostly) Passive Acid Farm
Move your territory so that you're near a polluted water source. There are some in the desert areas around Blackfell, for example, and the swamps near Greywater Camp. Once you've got territory near the water, you can start setting up the devices that will farm acid for you.
First, build and power a Water Pump in the polluted water source and connect it to power. Next, make a Reverse Osmosis Purifier and connect it to the Water Pump. That will automatically start to create impure acid from the polluted water.
A source of impure acid gets you halfway there; you need to purify it into Acid that can be used to make gunpowder or fuel. For that, you need a Brewing Barrel. Connect the Brewing Barrel to the Reverse Osmosis Purifier and make sure the impure acid is in the middle portion of the Barrel's menu.
You can make a use a Water Pump and Compact Water Filter to make pure water, which is the first ingredient you need to make acid.
You also need pure water to create acid. You can get some by building a Water Pump in the water and connecting it to a Compact Water Filter, both of which need to be powered. The Compact Water Filter will make pure water, which you can then add to the Brewing Barrel to create acid.
It's not exactly a hands-off method of farming acid, since you'll still need to move the ingredients around between the different filters, but you can dump impure acid and pure water into the Reverse Osmosis Purifier and go out to do other things while the acid is made.
It takes some grinding to get all this together, but once you have a regular source of acid, you can now make gunpowder. You'll still need two other ingredients, though: Sulfur, which you'll have to mine but which is available all over the place, and charcoal, which you can get by putting any logs in your Furnace.
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