One-up

1-up (also known as 1UP, 1-UP, XUP; pronounced "one-up") is a video game term that succeeds the player-character's gained extra life, allowing continuous play before game over. Because there are no universal game rules, specific 1-ups vary tremendously from game to game. However, they are very often rare and difficult items to acquire, occasionally requiring the player to demonstrate significant skill or risk an unnecessary death.

In certain games, it is possible to receive multiple extra lives at once. When this happens, the number of extra lives obtained sometimes changes the notification from "1UP" to a variant that reflects the total lives earned: two lives would be "2UP", five lives would be "5UP", and so on. Games that don't follow this rule often simply repeat the "1-up" notification in rapid succession concurrent with the number of lives awarded.

The term "1-up" appeared in American pinball games at least as early as the late 1960s, and perhaps earlier though its meaning then differed from its current definition. Early multi-player pinball games displayed "XUP" to signify that it was a certain player's turn (1UP for Player 1, 2UP for Player 2, etc.). It would also use this terminology to designate which score belonged to which player: "1UP" followed by a score indicated that it was Player 1's score, for example. Even then, however, the current concept of the 1-up was incorporated. These games often gave players multiple chances before one reached a game over. When a ball was lost in the gutter, the next ball was loaded and the game continued. If a player met certain conditions (such as a high score), they received an extra ball. Later, this concept was applied to arcade games. The inclusion of extra lives was very common in video games from the 1980s on, even in otherwise 'realistic' combat-themed games.

The use of the term "1-up" to designate an extra life first appeared in Super Mario Bros., where the player can gain an extra life in one of three ways:

The term quickly caught on, seeing use in both home and arcade gaming.

A number of games included an exploitable design flaw called a "1-Up loop", in which it is a possible to consistently acquire two or more 1-Ups between a certain checkpoint and the following checkpoint. The player can thus acquire two 1-Ups, make the player character die, and restart from the first checkpoint with a net gain of one life; this procedure can then be repeated for as many lives as the player desires.

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