SMILEs resemble the artificial Devil Fruit that Vegapunk created; they are colorful fruits resembling apples that have spots of a different color all over them, and those spots have another spot inside each of them.
The key ingredient required to concoct the fruit is SAD, a substance that only Caesar Clown knows how to manufacture. As such, to produce such a Devil Fruit requires Caesar's cooperation. The SAD is produced by Caesar, which then is transferred to the SMILE Factory in Dressrosa and processed into SMILE.
Due to the Tontatta Tribe's dwarves specializing in plants, they are forced into labor in producing SMILEs, under the false belief that it is medication for their sick PrincessMansherry as incentive to increase their rate of production; and dwarves' gullibility led them to believe the lie. It appears that the Tontatta can produce only one viable fruit out of every ten SMILEs, themselves noting the unorthodox fruit complicating the success rate. The spots seems to be an indicator for the fruit becoming SMILEs, and while mid-growing, the bottom quarter of the fruit lacks the telltale swirls. The manufacturing process of the SMILE Factory involves having luminescent sunflowers that provide light to the trees growing the fruits, while SAD is poured into the river. The river is led into irrigation canals on both sides which then channel the river under the trees in order to feed them.
With the factory and SAD supply destroyed, the production of SMILEs has stopped.
The SMILE is intended to grant the consumer the ability of animal transformation, much like a Zoan-type Devil Fruit. However, only one out of every ten SMILE fruits will successfully grant this ability. Thus, most people who consume one will not receive a power, and on top of losing the ability to swim, they become unable to express negative emotions, being forced to smile and laugh all of the time. The defective fruits maintain this side effect even after being partially eaten.
While normal Zoans can fully transform into an animal and an animal hybrid, successful SMILE users seen so far have demonstrated the ability to turn certain parts of their body into non-corresponding parts of the animal's body, such as Sheepshead turning his hands into sheep's horns and other gifters turning their hands, chest, or stomach into animal heads. SMILE users can still possess various traits and abilities of their animal, such as Batman gaining sharp hearing and Gazelleman being able to run very fast.
Like normal Devil Fruits, SMILEs render those who consume them unable to swim.Law has mentioned that being artificial, they do have their potential side effects. One such side effect is that instead of having animal features or limbs, some users will instead have an actual animal growing out of their body, as seen with Holdem's lion, whose head and arms are protruding from Holdem's midsection. Animals such as these will have a mind and will of their own, and this can be painful or even dangerous for the user as said animal may inconvenience, resist, or even attack its own host. However, as the animal half shares the same body as its user, it will share any pain its host receives, which will keep the animal from attacking its host too often. Others seem to have animals growing out of the top of their heads making the animals resemble hats or hair, as seen with fox and walrus SMILE users.
Notably, SMILE users are susceptible to Tama's Devil Fruit, meaning that if they are fed Tama's kibi dango, they will become subordinate to her.
SMILE can also result in multiple copies of the same animal appearing among its consumers, in contrast to the normal Devil Fruit which while can have multiple models of a certain animal, only one of each is ever witnessed due to the nature of Devil Fruits.
SMILE users have been seen with the abilities of a large variety of animals, from mammals to reptiles to crustaceans. While many of the fruits have not been named, it seems that the same animal power can be contained in multiple fruits, albeit with different traits manifesting from each one. It is unknown if these are "models" similar to normal Zoans or if they simply grant the same power with different applications.
Allows the user to have a scorpion stinger in their hair and six legs. Eaten by Daifugo.
Allows the user's arm to become a scorpion claw. Eaten by a member of the Grip Trio.
Elephant (ゾウ,Zō?) - Allows the user to have a elephant head in their belly. Eaten by Babanuki.
Monkey (猿,Saru?) - Allows the user to have four monkey limbs in addition to their own human limbs, and a monkey tail. Eaten by Solitaire.
Armadillo (アルマジロ,Arumajiro?) - Allows the user to grow an armadillo on their back, and enabling them the use the rough skin as a hardening shell for both attack and defense. Eaten by Madilloman.
Rabbit - Allows the user to have rabbit ears on their shoulders and have a the rabbit's face on their beard and rabbit's tail on his back. Eaten by Rabbitman.
Walrus - Allows the user's head to have a walrus' face and tusk on their hair. Eaten by a Gifter in Bakura Town.
Eagle - Allows the user to gain the head of the eagle and the wings on their backs and gain flying abilities. Eaten by a Gifter in Kuri beach.
Butterfly - Allows the user to gain butterfly wings for flying abilities and antennae on their heads. Eaten by a Gifter in Kuri Beach.
Fox - Allows the user to have a fox's head on their heads. Eaten by a Gifter in Bakura Town.
Ostrich - Allows the user's neck to gain an ostrich's neck. Eaten by a guard in Udon Prison.
Crocodile - Allows the user's arm to transform into a crocodile's head. Eaten by a Gifter.
‡: the character is no longer part of this group. Hovering the symbol may give further details.
After the SMILEs were created in Dressrosa, they were acquired by Kaido of the Yonko, who fed them to his crewmembers in order to turn them into Gifters. Kaido's dream is to have a crew entirely consisting of Devil Fruit users, and he has amassed an army of over 500 Gifters, while some of his Headliners have eaten SMILEs as well. The members of the Beasts Pirates who ate the defective SMILEs are known as the Pleasures. The Gifters use their abilities frequently during battle in order to increase their strength. However, after the SMILE Factory was destroyed, the Beasts Pirates stopped receiving SMILEs and so the production of new Gifters, as well as Pleasures, ceased.
The smiles of the people of Ebisu Town are but masks. Masks that can never be removed.
The shogun of Wano Country, Kurozumi Orochi, took the leftover defective fruits and put them in the leftovers that the poor citizens eat in order to force them to express constant joy, with the intention of maintaining a visage of happiness around the country.