In theatre, plays are composed of 1 to 5 act(s). An act
can also be used for major sections of other entertainment, such as film, television, variety shows, music hall, and cabaret.. Similarly, traditional platform game levels can be compared to scenes and fighting a boss the end of an act. In Super Mario 64 for instance, when Mario gathers enough stars, he can meet Bowser. Interestingly, "playing" the comedy follows the same rythm and breaks as "playing" a game. To achieve climax at the end of an act in the game, the death of a boss may be eventually followed by a cinematic scene. Actually, the following cinematic scene also helps the game designer launch the player on a new part of the story or recall the final objective and how to achieve it: "You have collected a new artifact, congratulations! Remember that to reach the bad guy, you need 3 more. You can find one here [blinking red dot on the map]".
According to Clive Thomson in a wired.com article,
a boss battle is the most mythopoeic part of gaming. Bosses stay in players' minds, and players often compare bosses, share their "favorite boss list" (as this gamespot thread shows) or exchange startegies. Players really like to talk about their game. As a consequence, players really like the boss system: a poll from The Escapist (N=129) shows that to the question "boss battles: yay or nay", 90% of the players answered yes and 10% no. I have previously detailed how boss monsters in a given level of Doom II or Dildo Tank become normal monsters in the following levels as the player has learned how to beat them. As an example of how much bosses can impact players, the Cyberdemon and Spiderdemon, the most impressive and powerful monsters that could be considered as bosses in Doom II, make noise when they move. From a game design perspective, the aim of the noise in Doom II might be to scare but also to warn the player. I think the noise contributes a lot to the "post-traumatic" state of mind the player is left after having played Doom II. As a player promoting the game to his friends writes,
Before too long, you may realize that you're actually becoming quite paranoid, or even frightened because this game is very intense. At this point you should probably take a break, because I don't want to get sued if you have a heart attack.. Similarly in Plants versus Zombies the player receives a letter from the evil Dr. Zomboss. While all the letters previously received from the zombies were stained with misspellings, the perfectly-spelled one from Edgar Zomboss (see screenshot below) shines with a very formal register. The player undeniably wonders what is going to change as a zombie that can spell words correctly enters the game.
Shadow of the Colossus (SotC), a very poetic game from 2005 praised for his atmosphere and original design, contains only bosses. As it can be read in the wikipedia entry for SotC,
the game is unusual within the action-adventure genre in that there are no towns or dungeons to explore, no characters with which to interact, and no enemies to defeat other than the colossi.. Beating each colossus requires its own strategy, but I will write about that later...
I strongly recommend the SotC OST.
I can hardly imagine a game with no boss. Games rely on a story, and the plot usually contains a conflict between the hero and his/her/its opponent(s). Just before the situation is brought back to normal (ie resolution), the player has to take part in a rising action to finally face the climax which consists of fighting the disruptive element(s). As the events happening to the hero are unusual, the player feels like he/she has to help the hero/heroine. This involvement can be seen at the back of kids' cereals box: the maze-games usually say "Help this guy find the exit" or "How is this girl going to find the solution?". For computer games, some NPC asking for the hero's help such as Toad in Super Mario 64 also make the player feel he/she is needed. Anyway, in the end, when the hero's task is done and everything comes back to normal (ie Falling action), the player can let the hero/heroine in his/her world and stop playing. But how can the plot of the game end if the player has no final disruptive cause to address? Killing the "bad guy that controls everything evil" seems an obvious solution, but multiple-endings games like Arcanum allow the player to choose his/her own solution. As a gamefaqs.com author writes,
you can even skip the last boss fight, if your have maxed Intelligence and Persuasion.
You can engage in a philosophical debate with the boss, and convince him that his plan is morally wrong. While the game provides the plot, the player should be the only one to decide how to solve it.