SMILE

The SMILEs (SMILE（スマイル）) manufactured by Donquixote Doflamingo are considered a success, and 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 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, and the fruits are in turn used by Kaido of the Yonko to create an army of over 500 Zoan Devil Fruit users, forming a three-way alliance. However, as they are artificial fruits, they still have their own risks, despite being a success.

Due to the Tontatta Tribe's dwarves specializing in plants, they are forced into labor in producing SMILEs under the lie that it is medication for their sick Princess Mansherry as incentive to increase their rate of production, and the gullible dwarves believed the lie. It appears that the Tontatta can only produce only one viable fruit out of every ten SMILEs. The bottom quarter of the fruit lacks the telltale swirls, which seems to mark the difference between a successful fruit and a failure. 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 has irrigation on both sides that channel the river under the trees to feed them.

It is unknown if this type of fruit shares any of the same weaknesses as natural Devil Fruits.

With the factory and SAD supply destroyed, and Caesar in captivity, the production of SMILE have stopped.

Members of Kaido's Crew known as "Gifters" are known to have obtained Devil Fruit abilities using SMILE. However, these abilities seem to differ greatly from those of naturally occurring Zoan Devil Fruits, since Kaido's "Gifters" are able to transform specific parts of their body (which somewhat resembles how Marco is able to utilize his Zoan devil fruit). This was first demonstrated by Sheepshead, who used his unnamed devil fruit ability to transform his arms into the horns of a ram.

Trivia

 * Doflamingo first mentioned SMILEs to Disco just before he abandoned the slave trade.