|Hit Type||Certain Hit|
|Remove Withdrawal||Event: Over Joyed|
|Remove Depression||Recover 100% HP|
This drug makes you feel nothing. Use it in a pinch.
The official description depicts it as a drug that makes you feel nothing. Some people, like Buddy, claim it to supposedly "make you feel good."
When Brad or any of his companions take it they get their health points fully replenished and they also get the "Joyed" status which raises some of their stats. Joy Addicts, like Brad, will always hit for critical damage while Joyed. However, this drug creates a dependency, making its user suffer the "Withdrawal" debuff, which decreases all stats, if it hasn't been taken for a while.
It can also cause humans to undergo a series of mutations when taken over time. Initially, the person loses awareness of their surroundings and begins to suffer morbid transformations on their bodies. These mutations usually cause the user's various body parts to enlarge, mainly the arms, legs and neck. Abdomen sections tend to excessively swell and fall around the body, similar to a large tumor. Each transformation is unique and it fully depends on the subject. Some mutations can also distort the human body in ways it could not undergo without bone breaking or organ constriction, such as Henry Wyatt's extreme body length. These mutants also take decisions and actions fully depending on their most inner desires and selves, making most of them violent, murderous and even cannibalistic beings. They represent a serious threat to anyone around them.
The beginning of the mutation process is foreshadowed by psychological alteration, most commonly a decrease in inhibitions and an increase in violent tendencies. An example of this includes Brad's brutal interrogation of Rick. In the second interaction with the Salvation Rangers, Blue states "I've been feeling very weird lately... having... violent... intimate thoughts..." a clear indication of the mental degeneration before his unfortunate transformation. This often causes the user to follow their innermost desires, such as amplifying Brad's desire to rescue Buddy and Buddy's desire for freedom to the point they become increasing violent towards anything that would impede them over time. These desires do not always cause the mutants to become violent, however. It some cases, the mutant can become "satisfied" (like the blonde mutant near the Area 3 campfire) or be too distracted to fight (like the mutant in the last room of the Fancy Cave of Area 3). Some also want to kill only specific people and then can be peaceful (such as the mutant on Resort Island, who is implied to be "done killing" after killing the other scientists in that room).
- One piece is always dropped by Doctor. Two pieces are always dropped by Beady, Charmy, Hawk, Herb, and Blue. Three pieces are always dropped by Georgy and Peter.
- Buzzo gives you some Joy at the factory and later in the game he makes you take 3 doses at the same time before he takes Buddy away from you.
- Area 3 Crossroads, three pieces of Joy can be found next to a Joy Mutant to the right of the campfire.
- Resort Island, inside of the hidden room, next to the Joy Mutant.
- Resting will temporarily remove the Withdrawal status effects.
- Physical violence seems to alleviate Joy cravings in addicts. After 20-30 turns in battle, Brad and other Joy Addict Companions lose the withdrawal effect. Joy Mutants also follow this. Most of those who doesn't attack when approached are surrounded by the bodies of those they have killed.
- If any Party Member uses Joy, the player will receive the "Joyful" ending. Likewise, if the game is completed without using any Joy (not counting Brad being force-fed) the player receives the "Joyless" ending.
- However, in the DLC LISA: The Joyful, joy use does not affect the plot at all, so there is no reason to abstain from using it, unless the player wants to significantly increase the game's challenge.
- Dingaling has said joy would not affect animals, but he's not entirely sure. 
- Unlike the name implies, the drug Joy doesn't actually make you feel happy at all. It just makes you feel nothing at all, both physically and mentally. To a person with immense emotional trauma and psychological problems or just plain depression, maybe feeling nothing at all is ecstasy.
- People turn into Joy Mutants when under physical and/or mental trauma, or when nearing death.