Dying for Symbolism

Let's say that you are watching a movie, and that the world is plunging into chaos. Of course the world is going to hell, but throughout all of it the main character's friend is still as hopeful and optimistic as ever. Eventually the main character feels that there is no hope left, and that the world is essentially over. How do the creators of the movie decide to show this? Well, nameless friend, you are about to be killed.

Essentially, this boils down to when a creator wants to convey some symbolism, and in order to do so someone either dies, is severely injured, falls ill, etc. It can apply to any character who happens to symbolize something. Insane character sacrifices themselves, means sanity is restored. Optimistic character falls into a coma, means optimism is wearing very thin, and so on. Death is often a popular option, due to being a somewhat safe bet to make an impact while not requiring being totally original. The character may die in the Crucified Hero Shot, often when their death represents something positive. I don't know why, but it seems like whenever symbolism needs to be conveyed, someone simply has to be attacked or killed.

Examples often symbolize something of the work or an aspect of it, be it an event, change in character, or even the franchise itself, though it can reach outside these boundaries. They are deliberate as well, so don't look to far into works lest you find faux-examples as in What Do You Mean It's Not Didactic?? They are meant to be fully intentional, and occasionally Word of God can confirm so. Rule of Symbolism may be employed in order to convey the symbol, especially in more abstract works.

See also It's All Junk, a very similar trope relating to the destruction of objects.

Anime & Manga

 * End of Evangelion Really, all of these are up to anybody's guess, but  This movie is virtually the definition of Mind Screw, so you may have a different interpretation.
 * Slightly more literal in Axis Powers Hetalia - the characters are the nations, so the death of a character is the fall of a nation (e.g. Rome). If the nation gets into dire straits (economic crisis, social strife etc.), the nation gets sick.

Literature

 * Lord of the Flies The makeshift society gradually goes into chaos, and when
 * In Camber of Culdi, Cathan MacRorie, Master of Culdi and Camber's heir, begs his king to release the human hostages taken after a tyrannical Deryni lord is murdered. Cathan is Deryni, but he argues for the common humanity and innocence of the hostages. Later, Cathan is literally.
 * Hedwig's death in the Harry Potter series is suppose represent the death of what remains of Harry's childhood.
 * itself is a symbol of Jesus' death, if the series is compared to Irish Catholicism, which J.K. Rowling is part of.

Theatre

 * In Shakespeare's Macbeth, Banquo is more conscientious than Macbeth and tends to point out what Macbeth ought to be doing. After Macbeth Jumps Off The Slippery Slope, he has Banquo killed; this represents the loss of Macbeth's moral conscience.

Video Games

 * In Metal Gear Solid 4 Guns of the Patriots Solid Snake's advanced aging and is used to hammer home the creator's message that the series is a Franchise Zombie.
 * In Red Dead Redemption