Health kits can either be found around the world, or crafted by Joel or Ellie. They can be upgraded to provide even greater healing capabilities by using training manuals. Health kits take several seconds to fully apply, but this can be done faster if the healing speed skill is upgraded.
If the player is low on health and has no health kits available, a non-playable character such as Ellie or Tess gives them one. However their health must be exceptionally low if on a high difficulty. They also can't be given one when on their own.
Health kits will initially heal up to 3 bars of health though, once they are upgraded by a training manual, they will heal up to 4 bars of health.
In Factions, health kits can be located on various parts of the map which the player can collect. They can also be crafted using alcohol and rags. Crafting health kits are better done as a last resort, since the crafting materials could be used to make Molotov Cocktails instead; health kits are common throughout all maps and spawn every two minutes regardless. The First-Aid Training skill decreases the amount of time needed to use a health kit.
Heath kits are crafted by combining one rag and a bottle of alcohol, which is the same combination to make a Molotov Cocktail. So players must choose wisely which one to craft. This was an intentional design choice by the developers to emphasize the scarceness of the resources and to show how every choice makes a difference.
It is generally better to not craft a health kit, since the player is gifted one most of the time and has a better chance of finding one than a Molotov.
- "I can find a bottle of alcohol and some rags and I can create a Molotov Cocktail from it. That's going to help me take out a couple of guys if I use it appropriately. Or I can use the same ingredients and craft a med-kit and that kind of lets me choose if I want to play more defensively and kind of have items that help me heal myself, or much more aggressively and I'm going to have items that help me kill and destroy in order to then progress and get out of this area." -Neil Druckmann, Creative Director, Naughty Dog.
- "We wanted you to be forced to make some choices in the world that showed how depleted the resources are." -Ricky Cambier, Game Designer, Naughty Dog.