The game uses a control system that differs from most other video tennis games on the market. Shots are performed by pressing one, or both, of the two main buttons (A or B), which make the ball spin in different ways. Pressing a button twice strikes the tennis shot with more power and spin. Additionally, pressing the two buttons in a different order can result in a different type of shot altogether, such as a lob or drop shot. Both buttons can be pressed at the same time to hit a very powerful smash shot. The longer a button is pressed before contact is made with the ball, the stronger the shot will be. The control system allows players of all levels to become familiar with the mechanics of the game within a very short time, whilst also encouraging advanced players to take advantage of the variety of shots offered to come up with different strategies for winning points. A total of seven types of shot are possible using only the two main buttons of the controller. These gameplay mechanics were later brought to the newer games of the "Mario Tennis" series. "Mario Tennis" received critical acclaim, with critics citing the accessibility and depth of the controls as being very impressive. The game physics and amount of content have also been praised. The Nintendo 64 version received "universal acclaim" according to the review aggregation website Metacritic. Dutch magazine "Power Unlimited" gave the N64 version a score of 9.1 out of 10, calling it very addictive, especially with four players. "Mario Tennis" sold over 200,000 copies within two weeks of its release. It became the eighth best selling Game Boy Color game in Japan, with 357,987 copies sold. A Game Boy Color version was released on November 1, 2000 in Japan; January 16, 2001 in North America; and February 2, 2001 in Europe. It features a wide variety of human and "Mario" characters for the player to use. The game also features mini-games such as a tennis version of a shooting gallery where, as Donkey Kong, the player must hit the banana targets on the wall to earn points in a set amount of time. A role-playing game mode appears in the Game Boy Color version, which is not in the Nintendo 64 version. In this mode, players begin as a rookie tennis player at the Royal Tennis Academy, who must build up their skill by leveling-up through training and practice matches before entering various tournaments. The aim of this mode is to be crowned champion at the academy, although the second part of the game involves the player competing in a tournament to ultimately face Mario, the best tennis player.