Goblin City

A famous video game that spans multiple genres such as sports, fighting, trivia, and puzzles, the popularity of Goblin City is unsurprising. A roulette (with the faces of the main characters in the anime) randomly decides the genre, game, and difficulty setting. The player is required to beat 4 out of 7 games in order to win.

Enemies:
Sports Goblin: A muscular and cheerful goblin who is the enemy for the Sports genre. He enjoys a good fair game, and cheerfully admits defeat when he loses. Defeated by Seaman in a game of tennis. "My name is Sports Goblin, I like to work out and flex my pecks."

Shooting Goblin: A cocky, boastful goblin who dresses like an aviator, who mockingly laughs at his foes before the match. He is the enemy for the Shooting genre. He is defeated by Genkai who blows up his plane.

Fighting Goblin: A quiet but arrogant demon who is the enemy for the Fighting genre. After Yusuke drank the growth potion, he is quickly defeated by him.

Puzzle Goblin: Only seen in the manga, this octopus like goblin is the enemy of the Puzzle genre. He was defeated by Yana copying Kaito.

Goblin King: Game Maou (Maou meaning Demon/Evil King) in the original Japanese, is the final boss of the game, who is fought after the player wins three times. Gamemaster foolishly chose this role while activating his powers, resulting in his death in correspondence to the Goblin King's own when Kurama defeated him in Three Sevens.

Games:
Tennis: A Sports game that plays like a typical Tennis simulation, with the joystick used to move and buttons used to swing the racket.

Battle Heli: A Shooting (Shoot 'Em Up) game in which the player takes control of an attack helicopter and must navigate through a barrage of bullets from enemy ship turrets, and an alien base, before facing the enemy goblin at the end of the level, who's in another attack helicopter.

King of the Hill: A Fighting game (though it is more reminiscent of a Beat 'Em Up) in which one must defeat weaker demons by striking them on the targets on their chests, then one faces the Boss of the level, who is a giant. The player must quickly drink the growth potion to become large and even the playing field.

Battle Quiz: A Trivia game. If one presses the button in the middle of the question, the answers will be shown even without the full question. If the button is pressed before the question even appears, the answer choices will be blank as well. According to Kaito, there are 17,000 questions in the General Knowledge category. Gamemaster can determine the order of the questions and answer choices after seeing the first five, based on an extremely sophisticated pattern of the questions' appearance.

Three Sevens: A Puzzle game resembling Tetris and Dr. Mario, in which one must line up the numbers on blocks to equal 7, or line up 3 7's.

Trivia

 * This game appeared earlier than the battle against Gamemaster in the anime. This was the arcade game Yusuke was playing when Kuwabara was fighting Seaman.
 * Known players of this game are, by the order of of skill: Yusuke (never beat it), Seaman (specializes in the Tennis game), Genkai (beat it a few times), Kaito (very high percentage of winning), Kurama (around the same level as Kaito), and Gamemaster (who has completely mastered the inner workings of the game). Sensui's level is unknown, but beneath Gamemaster's.
 * While the enemies in this game are referred to as Goblins in the English dub, they are genies in the original Japanese.