Melon

A Melon is a fruit, specifically a, found in tropical regions, such as Yoshi's Island.

Yoshi
Melons first appear in Yoshi, after the player clears levels 10 and 11 of the B-Type game, rewarding the player 500 points.

Yoshi's Story
Melons appear in Yoshi's Story, where it is the fruit of choice of the Yoshis. There are 30 of these in every level, all of which must be eaten (without consuming any other kinds of fruit) to achieve a perfect score. Each Melon awards the Baby Yoshis with a bonus 100 ♥ apiece.

Yoshi Touch & Go
Melons also appear in Yoshi Touch & Go, where they give Yoshi twenty eggs when one of them is eaten.

Paper Mario
They also appear in Paper Mario, where the adult Yellow Yoshi on Lavalava Island trades a Melon for one of Mario's food items. The requirement, however, is that the item be a recipe from Tayce T.. Melons restore 15 HP and do not sell well, even at Dry Dry Outpost.

Donkey Kong Jungle Beat
In Donkey Kong Jungle Beat, Hogs throw melons to attack Donkey Kong. Usually, they release three melons consecutively as part of one of their attacks. The player can clap while Donkey Kong is near a melon to punch or kick it back at the the Hog and stun it. Often, the Hog would shroud a melon in electricity and throw it much faster, requiring the player to clap one additional time to discharge the melon before sending it back. Donkey Kong can also force the Hog to release melons by clapping near the enemy.

A gigantic melon also serves as a goal in each regular level of the Melon Kingdom.

Mario Kart Arcade GP series
The Melon appears as one of Yoshi's special items in Mario Kart Arcade GP and Mario Kart Arcade GP 2. The Melon is a recovery item. Upon being used, it will remove all bad conditions from the user's kart, such as square tires, burst tires, or Thunder Cloud. In addition, the Melon provides a shield for approximately half a second upon being used. With good timing, this can be used to block incoming items or be immune to the explosion of a Time Bomb. In Mario Kart Arcade GP, a variant of the Melon known as the Melon+ can be unlocked. This variant greatly increases the duration of the shield the item provides.

Donkey Kong Barrel Blast
The Melon, known as Tasty Melon in this game, also appears as an item in Donkey Kong Barrel Blast. When used, it makes the player invincible, much like the Star from the Mario Kart series. When used by a Kong, the invincibility lasts longer. Unlike the Star, touching a player while invincible does not hurt them.

Mario Party 4
The fruit also appears in Mario Party 4 in the Bowser minigame Fruits of Doom. Here, it is one of the fruits that the players may give to Bowser to eat.

Mario & Luigi: Paper Jam
In Mario & Luigi: Paper Jam, Mario, Luigi and Paper Mario must race a Yellow Yoshi in Gloomy Woods in order to obtain a melon to give to Wiggler. Once Wiggler eats the melon, he moves out of the way, allowing the trio to continue through Gloomy Woods.