Permadeath, short for "permanent death," is a gaming term which describes the irreversible loss of a character upon their death. The term "permadeth" is used for game where you only get a single "life" or attempt to beat the game. Permadeath is contrasted against games where a character's death is not permanent, for example, because the game allows the player to save their game and reload after dying, or games where the player is given multiple lives or continues. In order for a game to be considered permadeath, there must actually involve a sense of loss. For example, if you die in Rogue, you can lose hours of progress, however, when you "die" in Tetris, where the average game only lasts a few minutes, not so much of loss is felt.
Games that use permadeath add an extra degree of loss when a character dies, and, depending on the player, this can be seen as a positive or negative aspect. For players who enjoy higher levels of risk, permadeath is seen as a good thing because it makes every action a gamble. However, for players who prefer games to be more light-hearted, permadeath is seen as a bad thing because it undoes all the effort that went into building up a character.
Traditionally, "permadeath" was only applied to role-playing games, but, recently, it has been applied to games of other genres. For example, Steam applies the permadeath tag to Risk of Rain, a platform shooter (even though characters are revived after each stage provided one character survives).
For the most part, I do not like games that use permadeath for two reasons. First, I dislike games where the player is punished severely for mistakes. Second, I don't like having to repeat aspects of story-based games.
These are categories for games that feature permadeath or optional permadeath.
Since the beginning of the genre, most pen-and-paper role-playing games used permadeath. Even those games that contain rules for resurrecting characters still have rules for permanent death. For example, in the rules of Dungeons and Dragons, when a character died, they are permanently dead and unable to be resurrected if they've been dead for awhile, their body can't be found, their body has disintegrated, or their soul isn't willing to resurrected.
Most early role-playing video games used permadeath as a mechanic like Moria, Oubliette, Akalabeth: World of Doom, Rogue, and Wizardry I: Proving Grounds of the Mad Overlord, but this mechanic slowly became less popular through the 1980s.
Despite permadeath decreasing dramatically from mainstream games by the 1990s, it has never really gone away. Occasionally, games are still produced which use permadeath like Darkest Dungeon and Realm of the Mad God. Also, many games are now incorporating optional permadeath modes like You Have to Win the Game.
In the early 1980s, permadeath in video games usually worked by simply deleting the character from the save file. However, this meant that a player could avoid permadeath by making frequent copies of their save file, and, if they die, restoring the save file. Although the player would lose all the progress they made since the last copy, it would certainly be better than losing all progress for the entire character. While bypassing a game mechanic is often seen as cheating in the gamer community, some games even encouraged this in the manual, like Alternate Reality: The City. The fact that players could just bypass permadeath anyway by "cheating" may have been the reason so many developers eliminated permadeath.