Prey Game Recycling Info

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Prey Recycling Info

Last major update 4 May 2019. Minor update 25 Dec. 2021 for Epic's free release.

Prey is PC sci-fi horror survival game in the spirit of System Shock and Bioshock.

While most aspects of the game have been covered in depth by other sites, I haven't seen any that detail some of the peculiarities of the game's Recycler. Everybody uses it all the time, but it has some little rules that are not obvious at first glance.

None of this info includes Mooncrash DLC data in any way. Sorry.

Recycling Overview

When you use the Recycler, it outputs your junk into cubes of four types of Materials:

  Organic (Org)
  Mineral (Min)
  Synthetic (Syn) 
  Exotic (Exo)

The game doesn't seem to have a unit of mass (kilograms or pounds or whatever), so I will call them, collectively, Materials (capitalized) here, when I mean "the amount of any or all of these four types". I also just call it Mass sometimes.

I recommend using the "OMSE standard" order for the four types of materials in Prey

  • Several places in the game present them in the order shown above. I am not aware of any place that does not.
  • But websites and guides use all kinds of orders. If you're trying to compare numbers, it can be very messy.
  • I recommend using the only order that appears in the game: OMSE

This work is a heavy collaboration with Evil (Vasile) on Steam

I could not have done this work without Evil's great XML support. I saw his guide to recycling on Steam and we started talking. We bounced ideas around for weeks - months - as he pulled the raw data out of the game files, reworked it some, and then I refined it.

Here's Evil's short guide on how to extract the prey game data:

The game stores its data in the *.pak files located in "Steam\steamapps\common\Prey\GameSDK\".
The files are basically encrypted ZIP archives, to decrypt them you will need a decryption tool. You can get it over here:
If you want to look at the recycling data yourself, you will need to decrypt the "GameSDK\GameData.pak" file and the "GameSDK\Precache\patch.pak"
In the decrypted archive, you will want to have a look at the *.xml files located in "libs\entityarchetypes\" - GameData.pak contains the base files, and patch.pak contains the latest patched data.
But before you can read the *.xml files, you will have to decrypt those too! Luckily, a few posts down in the same thread, you can find the XML decryption tool too!
To use the decryption tools, just open up the command prompt, and launch the tool with the input and output file as arguments as in this example:
D:\Test\PreyConvert_003\PreyConvert.exe "D:\Test\In\GameData.pak" "D:\Test\Out\"
Same goes for the xml decryption tool!
Since extracting all the files manually one by one is tedious, when I first delved into the game's recycling data, I made myself a GUI tool that launches the decryption tools automatically for all the given files in a folder. I've now uploaded the source files for this tool here:

Game Data on Items and Recycling

This spreadsheet lists all the items in Prey that can be picked up and/or recycled, and the amount of materials you'd get. Even furniture (with a recycling grenade):

If you convert Excel to something else and the format of the Cover Notes worksheet is wonky, here's a PDF of it

The original intent was to answer a gameplay question like this,

I don't know where the Recycler is on this level yet ... My inventory slots are full and I sure am finding a lot of banana peels... Should I drop my one Corroded Coil and use its slot for Banana Peels instead?

You can use this to see how many banana peels and corroded coils are on that level. And how many materials you get from them.

We also threw in lots of item material and other properties, for anyone interested.

Fun Facts from the Item Recycler data

stats in this section are for base recycling amounts, without any mods to increase recycling output

Theoretical maxima of how many materials you can put in a stack

The item that can make the single-largest stack of material in the game is Neuromods. You can have a stack of 1,000, and they have a total of 1.75 materials each. That's a grand total of 1,750 materials, if you ever got a full stack.

  • Many of the biggest-stack items are like that: You wouldn't actually want to hold onto all your neuromods through the entire game
  • The second most-stackable is the Typhon Cortex (1000 x 1.50 = 1,500)
  • Who'd want to carry around a thousand Corroded Coils (1000 x 0.60 = 600)? Except for a personal challenge.

More realistic for a personal achievement would be ammo or supplies. Psi Hypos are tops here (1000 x 1.00 = 1,000). With the right mods, I didn't actually use many of the Psi Hypos. But of course, I never got anywhere close to a thousand.

  • Stuff that is officially Trash is also about the best. Corroded Coils top the list, followed by Fried Hard Drive (1k x 0.57 = 570). But who wants to haul around stacks of Trash the whole game?
  • Likewise, lots of food and drinks could in theory stack to 100 or 200 materials total. (They allow stacks of 1k.)
  • More realistically, the following ammo all stacks to 10k and weighs 0.20 each, for total stacks of 200 mass:
Disruptor Batteries
GLOO Canister
Q-Beam Cells

The worst in terms of allowing a big stack (1k) but little mass if you reach it, are Lemon Peels and Used Cigars. These only weigh 0.05 each, and would only make a max stack worth 50 materials.

You'll probably never get anywhere close to the max possible stack for anything in the game. With the possible exception of two things:

  • The ammo, grenades, and supplies that have strict limits (often 10; see the Item_Stats worksheet tab)
  • Or if you camped out at a fabricator just for the hell of making a gazillion of something like ammo

Practical maxima of stack material

In terms of how often items are actually found in the game (not their theoretical max stack size),

  • Neuromods and Exotics Materials (cubes) are the highest at ~51 and ~25 (respectively) in total mass you might could get in a stack if you held onto them all. (To see this, sort the Items_By_Level worksheet on descending Max Total Material, then filter for Level = ALL and Pickup Type = Item Totals.)
  • The more realistic goal (of things to hang onto) is Disruptor Batteries. You can find them up to 110 times (your actual number will probably be quite lower), and you get 40 to 90 each time. Each battery is worth 0.02 materials.
  • Psi Hypos are next with a possible 231 appearances. They're worth 1.00 materials each.
  • Factoids: There are a possible 43 Wrenches, 183 Medkits, and 293 Suit Repair Kits.

Can you recycle for profit?

Can you fabricate something, then recycle it, and get more materials out than you put in?

As you might expect, the answer is No. But I tested it, so now we know for sure.

The closest you can come is recovering 97.5% of the fabricator input. This is for Disruptor Batteries if you have both recycling mods (Engineering Materials Expert neuromod +20% and Foy's Adventurer's Toolkit v1.x suit mod +10%) for 130% recovery of the fabrication materials.

If you want to see the math, look at the Profit worksheet in the Prey data spreadsheet.

Recycler binning

Certain rules govern the Recycler's output:

  • It will never output more than 16 blocks. If you are less than 15+ total for all materials, there will be less than 16 blocks.
  • The minimum individual block size is 1.00, except for remainders.
  • It always outputs blocks with multiples of .25 (1.00, 1.25, 1.50, etc) except for a final remainder block (if any). This has been seen for up to a full-block size of 4.25 mass (a total approaching 68 total mass in the 16 blocks).
  • Full blocks are square, and the remainders are round. In both cases, their colors correspond to the type of material.

For a quick demonstration, if you have the Materials Expert neuromod (+20% recycling), try recycling 166 of 9mm ammo. Then try 167. The math:

  Pistol Bullets base mass: 0.06 Min, 0.02 Org each
  Bullet mass with Materials Expert: 0.072 Min, 0.024 Org each

  For what number of bullets does the mass total equal 16?

  16 = 3x + 1x, where x = the Org mass of one bullet (0.024)
  16 = 4x
  x = 16 / 4 = 4.00

  How many bullets to make 4.00 Org mass?

  4.00 / 0.024 = 166.667

This is the cut-off point where the full-block mass goes from being 1.00 to 1.25.

  For 166 pistol bullets, you get 11.95 Min and 3.98 Org, total 15.93.
  That's 16 blocks of: 
     12 Min: 11 x 1.00 + 1 x 0.95
      4 Org:  3 x 1.00 + 1 x 0.98
  For 167 pistol bullets, you get 12.02 Min and 4.00 Org, total 16.02.
  That's 14 blocks of: 
     10 Min:  9 x 1.25 + 1 x 0.77 (12.02)
      4 Org:  3 x 1.25 + 1 x 0.25  (4.00)

Notice how the total number of blocks dropped to 14, because the new block increment of 1.25 left some room to play with.

You can do similar math for anything else.

I have not studied the edges of what would happen if you deliberately tried to push the equation of what gets rounded if you had X of one element and Y of another equaling Z in total, where it presented a challenge to rounding because Y was pushing the envelope of the block size, but X wasn't. I imagine they got this right.


I didn't want to bother having a wiki comments section or forum on my tiny wiki, so here's a Reddit thread for comments and discussion. And another one Christmas 2021 when Epic gave the game away free.

You can also send a comment directly to me (see About & Contact Me in the upper left navpanel of this page).

Also see my hella PC games analysis page.