Gemu Gemu no Mi

The Gemu Gemu no Mi is a non-canon Paramecia-type Devil Fruit that allows the user to transport other people into a game-like world, being able to decide on the genre of game. It was eaten by Dama's Tablet.

It is unclear if this Devil Fruit actually exists in the One Piece world, or only in Mr. Kuromaku's pseudo-world.

Etymology

 * "Gemu" is the Japanese pronunciation of the word "game".

Strengths and Weaknesses
The main strength of this Devil Fruit is the ability to significantly decrease your opponents strength, as well as abstracting fights to a position where the user cannot be harmed. Due to the nature of video games, it will also empower weaker "characters", allowing for temporary powerups.

Aside from the standard Devil Fruit weaknesses, the only other known weakness is the time it takes to trigger the ability; the user must select a "boss" character, select the genre and stage, then select a "player" character.

Usage
Dama uses the his tablet's abilities to equalize unfair fights, using it to transport Silk Road and Arlong into a fighting game, as well as transport the remaining Fischer's members into a platformer game with the Arlong Pirates as enemies.

The user of the fruit has partial control over the "player" character, who's able to perform actions they aren't normally capable of.