Deathloop Residuum Infusion Guide: how to keep your weapons every loop

Using a powerful ability in Deathloop against an enemy
(Image credit: Arkane Studios)

f you want to get anywhere in Deathloop you’re going to need to start engaging with Residuum Infusion. 

This helpful system allows Colt to maintain items between runs, which is crucial in the late game as you start to need better upgrades, powers and weapons to take down hordes of enemies in quick succession. Infusion will quickly become a key factor in helping enact your wacky loop-closing plans, so it’s best that you know everything about it. 

In this guide, we’re going to show you how to unlock Residuum Infusion in Deathloop and then talk about all of the lesser-known features of the system so that you leave with all of the key knowledge. With our tips, you’ll be well on your way to killing all of the Visionaries and breaking the dreaded time loop that Colt is stuck in!

How to unlock Residuum Infusion in Deathloop 

You’ll have to play through Deathloop’s tutorial in order to unlock Residuum Infusion. The game’s opening is quite long and slowly introduces you to the game’s systems, from Slabs to Districts and everything in between. After a few hours, you should be tracking a lead called ‘Ubiquity’ where you have to hunt down Wenjie at The Complex. You can’t miss it, so just keep progressing until you’re prompted to head there. You’ll have to find and kill Wenjie in her lab to unlock Infusion and we’ll leave that battle as a surprise as not to spoil anything for you!

Once she’s dead and gone, you then have to pick up the Portable Harvester nearby and steal the slick gas she leaves behind. With this in hand, activate the signposted experiment and you will unlock the ability to infuse your items. This allows you to pay a certain amount of Residuum so that you won’t lose the items you want to keep at the end of a loop.

Taking on enemies in Deathloop

(Image credit: Arkane Studios)

How Residuum Infusion works in Deathloop 

Now that you’ve unlocked Infusion, every time you return to the tunnels after completing tasks in a district you’ll be prompted to infuse the items in your inventory. The items you can infuse include weapons, trinkets, slabs and slab upgrades. Item rarity will affect the amount of Residuum you need to infuse a piece of kit.

With that in mind, you’re going to need a lot of Residuum to infuse your favourite Deathloop items. The main way you can earn Residuum is by killing Visionaries, as they leave behind huge deposits of Residuum that Colt can harvest. As you walk through the maps you should also be on the lookout for small Residuum deposits emanating from random items. They will emit that slick chromatic gas and make noise when you get close, so they’re hard to miss. You can also sacrifice the excess items in your inventory to earn enough Residuum to infuse a key item in the infusion menu between runs. 

When Colt dies and uses a Reprise charge, he will also leave behind a massive Residuum stain that you can retrieve, kind of like Dark Souls. It will be marked on your map once you come back to life so the deposit is easy to retrieve.

Players should focus on infusing slabs that they earn from killing Visionaries, as this will unlock those powers permanently so they can be used in future runs. The same goes for any slab upgrades, trinkets or special guns that you find in Deathloop. If you don’t want to lose it, infuse it! It’s also good to know that if you infuse something at Noon after a Morning run, you won’t lose it when the loop ends at the end of the day. So you can safely drop or swap out any infused items and they’ll be waiting for you the next morning.  

Jordan Oloman

Jordan Oloman is a journalist and documentarian with experience across the pop culture/tech spectrum writing reported features, reviews. news, guides, op-eds and more for a wide variety of outlets. He is also an affiliate streamer on Twitch and have previous experience in scriptwriting, podcasting, game consultation and creating video content.