After AlphaDream developed and released their very first video game title, Koto Battle: Tengai no Moribito for the Nintendo Game Boy Color only in Japan, Nintendo wanted AlphaDream's permission to develop an entirely new RPG with them, titled . It was finished and almost ready to be released for the Game Boy Color in Japan, until Nintendo released the Game Boy Advance to make the Game Boy Color obsolete. After noticing that, AlphaDream decided to redevelop and rename Gimmick Land as Tomato Adventure for the Game Boy Advance. The differences between Tomato Adventure and Gimmick Land are the names and the quality of the graphics and audio. Only two screenshots of Gimmick Land (one of them shown on the left) were released to the public by the developers. On the release date of Tomato Adventure, Nintendo and AlphaDream announced a contest where twenty lucky winners won themselves 1 kg of famously sweet tomatoes from the Kochi Virtue Valley area. The contest ended on February 28, 2002.
The story takes place in a land ruled by and intended for young characters: the Ketchup Kingdom. The protagonist is a hare-like boy in the blue clothing name DeMille, who lives in a school bus with no wheels in a village on the outskirts of the Ketchup Kingdom called Kobora Village. DeMille is an outcast because he dislikes tomatoes. As a result, DeMille and other kids in Kobora who dislike tomatoes are referred to by people who like tomatoes as "Droppers", which are people who are banned and left locked up in Kobora Village until they like tomatoes. When he was watching television, he saw that the main antagonist, King Abira, was celebrating a holiday called Tomato Day, while showing his project he created called the Super Cara-Cooker, a laser-like gun that transforms people, places, and things into dolls, toys, and playgrounds. Then, DeMille's television became severely damaged, while he went to his neighbor and friend, Seremo, and asked him if he would fix his television set. Then Seremo said he will, while he gave DeMille his first Gimmick, called the Gear Yo-Yo. After Seremo taught DeMille how to use it, DeMille's girlfriend in the pink clothing, Patharan, came to tell him that she wanted to show him her gift she got from someone at the top of the Toy Ruins, the Gimmick Robo, but then it wasn't there when they arrived. Then, two purple creatures with zippers on them, Gorikki and Burikki, captured Patharan with a hook, DeMille grabbed on to her while being pulled up to the airship, called the Carorna No.2, piloted by Gorikki and Burikki. As soon as DeMille and Patharan came aboard the airship, Gorikki and Burikki received a call from King Abira, who told them to bring Patharan to the palace and drop DeMille out of the airship. After DeMille fought Gorikki and Burikki, they dropped DeMille from the airship into the Tomato Pond, then he walked and noticed that he was standing near King Abira's home, the Gimmick Palace, a tall, red, tower with a tomato-shaped top. When he decided to enter and save Patharan, he encountered a wall that he cannot pass through. Then, a mole named Rereku told him that in order to pass through the wall, DeMille had to defeat the six Super Kids and obtain the six key items called Toy Parts. While DeMille went on his adventure, he encountered some people who joined forces with him to defeat King Abira, and save Patharan and the entire Ketchup Kingdom. His parters in order of joining him are Aretha, Sofubi, and finally, Rereku.
The most significant part of this game is its battle system. Instead of the traditional fight and magic commands, players would fight using toy-like weapons called Gimmicks.
Every Gimmick has their own mini-game. For example, when using the "Gear Yo-Yo" Gimmick, which belongs to the Time category, players have to press a button when the edge of the bar is in the red mark within the given time limit. If players successfully implement the maneuver, they'll inflict a critical hit. Players can also adjust the difficulty of the Gimmicks they have to inflict more damage. As another example, in order to correctly use the "Snea-Car" Gimmick (which looks like a shoe-shaped car), players have to press the right combinations of directions and buttons the game shows. In the easiest mode, players are thrown a sequence of 4 icons consisting of directions and buttons at a relatively slow pace. When players bump the difficulty up to max, its feeds the players 6 icons at blazing speeds in a very narrow window. Most weapons and items in several other RPGs can be overused by players, but in Tomato Adventure, Gimmicks have a limited amount of usage similar to most weapons and items in the Fire Emblem series; however, once players use up a Gimmick, the usage count won’t reset until all of the Gimmicks equipped by a character are completely used up. In addition, when DeMille's first partner Aretha joins him, a gauge feature that fills every time a Gimmick is successfully used becomes available to use. If players successfully charge up the gauge while passing an arrow in it, they will be able to do a special extreme attack when a gear lights up. When fully charged, two gears light up, making players have the choice to use another special extreme attack; however, if players fail to use a Gimmick correctly, the gauge will become empty, while players will have to start it all over.
Gimica is a special card game that can only be available when the player talks to Gimicamania at the stadium in Ois Town after the player defeats the third Super Kid. However, there are also some other characters that the player can either duel with or receive a new Gimica Card from.
The object of this card game is to make the opponent have less HP than the player's HP, or drop it to zero. There are two kinds of cards:
Player must put his/her Gimmick Cards at a higher color rank than his/her opponent, however, green beats blue. If both players have their Gimmick Cards on the same color rank, the player who has more attack points in his/her Gimmick Card will attack the opponent. If both Gimmick Cards' attack points are equal, it becomes a draw. If the player's opponent is at a higher rank, the player must either make his/her Gimmick Card's attack points the same (or nearly the same) as the opponent's in order to receive a small amount of damage, or move their Gimmick Cards up to the same color rank as the opponent's Gimmick Cards.