Serum

Any orally-administered mutagen can be concentrated into a higher-powered serum. Researchers in the labs discovered that this gave them more bang-for-the-buck when administering the mutagen, at the cost of significantly higher demands on the subject's system. There were unconfirmed reports of significant behavioural side-effects in subjects exposed to significant amounts of particular serums, though the research in that area was regrettably halted when the Cataclysm struck.

Crafting

As with mutagens, you'll need a recipe to convert your favourite into a serum. Most specialized serums are found in their own lab journals, while more generic ones are found in high-level chemistry books. The process requires Cooking skill 9-10, depending on the base product's level, and cooking the chemicals down takes a while. They also require rare tool qualities only found on lab equipment—concentration, and fine distillation. For the recipes, look in the item browser.

Once you've got your serum, you'll need a syringe to inject it. Syringes are not consumed.

In general, injecting yourself will provide you with a minimum of 3 and a maximum of 5 mutations. Certain serums provide less mutations. You'll take a Hunger, Thirst, Fatigue, and Pain hit based on the amount of mutations you gained; more mutations means a harder hit. The process is not good for your Health either, so it's good practice to eat some healthy food or shoot up a gamma globulin shot‎ afterward. Serums are also highly addictive, so it's generally not a good idea to inject more than two at a time.

Why use serums?

Serums are generally more cost-effective than their associated mutagens, giving you by far more mutations per shot, and can take you over the threshold. However, they do take a lot of additional time to craft, and tools you may not have. In addition, their toll on your body is significantly worse.