Answer: The legend of Zelda
Early arcade game was intended to be played in a single sitting, often as a kind of skill test where the player tried to get as far as possible and / or get the most points. When video game consoles arrived, they emulated the same kind of gaming experience you would find in an arcade-you played as long as you could get as high a score as possible.
The introduction of Nintendo's Legend of Zelda 1987 (North America and Europe) was a radical shift in console games. The Gold Legend of Zelda cartridge contained an internal battery powered by a small RAM chip that saved the player's progress. For the first time, console players can save the game at any time and return to the latter. Games were no longer limited to a race-to-finish delivery. Because of this, the size of the game's universe and game complexity could be greatly increased because the designers knew that players could complete the game over several sessions in their spare time.
The expanded game and the rich environment were a hit with players. The legend of Zelda was the first Nintendo game to break a million sales mark, eventually sold 6.5 million copies and is one of the most famous video games in history.
Image courtesy of Nintendo.