Much like other survival horror games, The Callisto Protocol puts inventory space at a premium. Some of the game’s scariest moments come when you’re forced to pick and choose which items to carry further into Black Iron Prison and its surrounding habitat areas — and which to leave behind completely. As you’re playing through the first several chapters, you may be wondering how to increase inventory space to carry more.
When you begin The Callisto Protocol, you’ll have six inventory spaces for items like energy converters, ammo, and health packs. Found on the right side of the Inventory Menu under the Items label, this space does not include weapons. Instead, weapons are stored in a separate, non-upgradeable area labeled Arsenal on the left side of the Inventory Menu. Likewise, important story items like gate fuses do not take up item inventory space.
To increase inventory space, you’ll need to make it to the end of Chapter 4: Habitat and the beginning of Chapter 5: Lost. Here, during a cutscene bridging the two chapters, you’ll gain access to the space suit seen in all of The Callisto Protocol’s trailers and marketing. This space suit increases your inventory space from 6 slots to the maximum of 12 slots.
Unlike printing and upgrading weapons at the Reforger, you do not have to do anything else to get more inventory slots.
And that’s all you need to know about increasing and upgrading your inventory in The Callisto Protocol. If you’re on the hunt for all of the game’s collectibles, head over to our audio log and data bios guide. If you’re wondering how to get all of the weapons (because you’re definitely going to want the Riot Gun and Assault Rifle for the game’s final chapters), we have a complete locations guide right here. We also explain what Energy Converters are for.