Land to the NES. Since the Game Boy title was aimed at beginners and the NES player base was more experienced, Sakurai chose to create a new game instead. As a result, little of Kirby's Adventure is based on Kirby's Dream Land: "Even though we could use the same pixel art for Kirby, when it came to capacity and what was possible, all that expanded greatly with NES." HAL Laboratory wanted to expand Kirby's existing repertoire of moves. Kirby's Dream Land was designed for beginner players, but as a result received criticism from more experienced players looking for a challenge. With Kirby's Adventure, Sakurai wanted to retain simple gameplay, but improve it so skilled players would enjoy it. This led to the conception of the Copy Abilities, which the team hoped would allow players to experiment and improve the replay value. HAL Laboratory created over 40 Copy Abilities, after which they selected their favorites to include in the final game. They also added minigames because they feared that Kirby's expanded set of moves would give players the impression that Kirby's Adventure was a difficult game. They were designed to be simpler and easier than the main game. Kirby was also given the ability to run faster and perform a slide attack to increase the game's pace. Programmers were skilled with squeezing out power of the ten-year-old NES hardware by 1993. Kirby's spit attack was made stronger if multiple enemies or objects were inhaled, something they had wanted to implement in Kirby's Dream Land. Kirby's Adventure is the first game to depict Kirby in color. Sakurai had always envisioned Kirby as pink, but the Game Boy's monochrome visuals rendered him white in Kirby's Dream Land. The other staff were shocked when they learned Kirby was pink. Kirby's sprite was also made larger after players complained he was too small in his Game Boy debut. While backgrounds are typically designed by someone experienced in game mapping, for Kirby's Adventure, HAL Laboratory had an artist draw pictures of the backgrounds, which were then handed to the mapper to work into the game. According to Saitou, they were supposed to be "pretty enough just to look at on their own." Kirby's Adventure also marks the first appearance of Meta Knight, who appears as an unnamed boss in one of the game's levels. The game was published by Nintendo in Japan on March 23, 1993,