: How do I add tension to a story, when the reader knows the MC survives? To clarify: There are two parts to the book (or I might split them into separate books), one with my main protagonist,

Technically, the survival of the father in the prequel is not guaranteed by his presence (or apparent presence) in the first story. The most obvious way of accomplishing this is to have the first story be "it was all a (pleasant) dream".

This could be presented in the title of the first story (e.g., An Heir's Choice: The Dream of Argoth) in which story "dream" could refer to the father's prophetic dream which started the quest and to the father's aspiration for his son (e.g., that he would be a hero like he was) but also to the story itself in the context of the prequel.

For example, the father's quest could be to destroy his ancestor's crown to end the threat of a great evil that entered the world by that ancestor's choice. Near the end of the story, the father could be spending the required three nights in the Chamber of Dreams before entering the King's Vault that holds the crown. Perhaps halfway through the story, the father discovered that ending the evil would require his death, and the first night's dream confirmed this; putting on the crown and taking responsibility for the ancestor's choice ends the evil and his life. The second and third nights' dreams could be presented in the text as a summary of the first story, where destroying the crown by casting it to the ground, rejecting the benefit from the ancestor's choice, banishes the evil for 343 years. The prequel could end with something like:

At last he held the crown, the weight of centuries of evil felt strangely light in his hands. He made his choice.

With such an ambiguous ending, the first story could be actual history (as revealed by the dream) or a future that might have been. (Incidentally, a third novel (e.g., An Heir's Choice: The Hard Path) could present the alternative future in which the evil was ended rather than banished.)

Even with the title hint, it might be difficult to write such stories. However, unlike the "it was all a (bad) dream" cliche, the detail and attractiveness of the story would make it a very powerful, real temptation for the father and less of a cheat to the reader.

Another possibility would be that his father is not his father but rather, e.g., his uncle. In the prequel the father's brother could witness the father's death and swap identities ("my brother gave his life for me and for all the Land of Crestern"). The first story might present hints that his father is not his biological father, but this fact need never be revealed in the first story. (A third story might reveal this fact.) A heavy emphasis on paternal and fraternal love in the first story might strengthen the end of the prequel.

Resurrection is a third possibility. The father might die with the full assumption that he is leaving his son an orphan, but he might be brought back at great cost (which might also be why this fact is never mentioned in the first story but it might be hinted by the father saying things like "I owe her my life and more", "life is not the highest good", "one cannot always see the beginning or the end from the middle").

Retcons are difficult to write well. Even with hints and ambiguities in the first story, the reveal in the prequel can easily seem like a cheat or just an unnecessary confusion to some readers. Making the first story clearly matter (using the attractiveness and reality of the dream to emphasize the temptation, using the brother/uncle's love and dedication as an adoptive father in the first story to emphasize the fraternal love in the prequel, or using real death (with fear, pain, and grief) and the price others were willing to pay to bring him back to avoid a perception of insignificant death) is one way to reduce audience disappointment.

Of course, none of these actually solve the problem of perceived risk since the readers of the first story will assume that the father survived. As the other answers state, the general outcome of success and survival need not be the primarily source of dramatic tension (happy endings are commonly expected). Death and outward failure are not the worst fates possible. In high fantasy, personal honor is likely to be highly valued ("Gawain and the Green Knight" has Gawain survive but at the cost of dishonor even if he was judged more honorable than other knights; or quoting Aral Vorkosigan's statement in A Civil Campaign (Chapter 15), "There is no more hollow feeling than to stand with your honor shattered at your feet while soaring public reputation wraps you in rewards. That's soul-destroying. The other way around is merely very, very irritating.").

How the character survives and succeeds (what cost, what heroic choice or determination, what clever device, what unexpected intervention, what flaw in the villain, etc.) can easily be more significant than the outcome.

In addition, when one is drawn into a story, facts and assumptions can be forgotten in the immediacy of the action as one's perception is guided more by feeling than by rational consideration.

Finally, dramatic tension is not the only reason people continue reading a story. For example, satisfaction in the felt truth of a story need not depend on the unexpected (people do re-read stories).

---

(0)

It's quite possible to feel tension and doubt about the outcome of a book you've read before many times --if you become immersed enough in it, you suspend your disbelief, and forget that you already know what happens.

So my advice is to work on making this the best and most immersive book you can, and don't worry about what the readers may already know about the outcome.

---

(0)

Tension is, technically, the struggle between protagonist and antagonist when they both want the same thing.

Readers will experience a variety of emotions, vicarious and sympathetic, when they become invested in the outcome of a story and its world.
As JM Straczynski put it, not knowing what happens later is a minor aspect of the drama in any story. It matters less whether the main characters will live, or whether they will discover the bomb and disarm it before it explodes, than how exactly they respond to the dilemma — how it affects them.

It matters more, to the reader, whether they — the reader themself — get caught up in the story each time they read it.
If your characters are vivid, and if their interactions and choices seem genuine, then the reader will enjoy each reread as much, or more, than the first read.
You have the novelty versus treasury trade–off, of course, but any good author of a story knows that novelty is cheap — really, I wish that they weren't called “novels” any more. If you expect it to be the chief attraction of your story, then in a few years your story will end up out–of–print and scattered throughout secondhand bookstores in the ten–dollars–a–bag cabinets.

To simplify at the loss of some accuracy: most readers, except those who don't really care to read at all, care more about the story itself than they do about the outcome of the story.
Most of that concern is earned on an emotional level, yes, but it can be done intellectually and aesthetically too.

---

(0)

The reader doesn't actually have to know that the father survives, not past a certain point anyway, if you don't specifically identify the MC's mother then the MC may already be on the way before we ever meet his father. You need not state this categorically, in fact better if you don't, but it can be strongly implied that the MC has been conceived before the father goes to war. Thus you need not necessarily remove his death as an option within the narrative.

Also as other's have aptly pointed out death need not be the highest stakes under the circumstances.

---

(0)

This is a novice mistake. If the worst thing you can think to do to a character is kill them, you're not thinking hard enough. There are all sorts of ways to get hurt. Love, family, friends, status, and property are but a few things that can be lost or threatened. Tension is conflict, and conflict can be found at all scales, tiny and large.

Tension, A Series of Definitions

The state of being stretched tight
Mental or emotional strain
A strained relationship
The relationship between conflicting ideas, qualities, demands, or implications.

How Do I Tension?

It's right there. You create a conflict. Conflict begets tension. Conflict of any size, that is important to your readers introduces tension into the story. It's not any more complicated than that, but of course picking the right conflicts is itself an art. You know if you're doing it right by the following

Literary Tension.

Tension is a measurable feeling of dissonance that a reader feels, that is in relationship to their expectations and hopes and feelings in a given moment in a story.

This often looks like it is caused by the immediate mystery of what might happen next; but, it is actually connected to the feelings you are generating within a reader; which might include the excellent feelings of expectation, uncertainty, and anxiety, but are not limited to those feelings.

Tension: Death

Death is a tense experience. It's traumatic. It is the thing many people fear the most. If you give it gravity & weight & make the thing that is dying familiar and loved, then the tension at the moment of the death, leading up to the death and even after the death is quite high. This correlation to emotion is not a mistake; tension is the measurement of emotion. That is why we value it in stories.

You can have near perfect information about an oncoming death being inevitable; and that will increase tension if you like the character and DO NOT WANT THEM TO DIE. That is the conflict. Your expectations/desires as a reader being in conflict.

Tension: Love

Can you have tension when you know two people will get together? Yes, if you ultimately don't know how or if the thing that you want ends up being different than the thing you know will happen. IE, you can know that two people end up happy together because you've seen the sequel. But, if option C is a much more likable person and leads to a much more likable relationship but can't be had for certain reasons, you may find that you actually want A & C to be together even though you know A & B together is just fine.

Of course it's much easier to inspire tension if your reader doesn't know whether A will end up with B or C; and D is threatening some sort of villainy to boot.

Tension: Situational

You may consider something like a power outage, which clearly ramps up the readers anxiety to be inspired by the lack of knowing what will happen. And it's true that this will happen; but this again enforces the wonderful definition above. Tension is the measurable feeling of dissonant emotions in a time and place within a story. In this case we're tweaking anxiety, perhaps fear; or even annoyance if we know who caused the power outage and feel some frustration towards that person. This type of anxiety might not play a role in our climax, but it can be a good thing to push interest early in the story before you've formed bonds with characters that can be pushed for higher levels of tension.

Tension: Etc

These were not nearly all forms of tension because tension results from the infinite spectrum of conflict. How do you tension? Take anything, set it at odds with anything else. The more that's in conflict and the stronger the emotion you are tweaking the higher the tension.

Your Problem

The tension in your prequel will have to do with reader expectations. You'll need to give them the hope for a better outcome, but serve them something inferior. In that way, even though they know the father will come out of this, they won't know in exactly what ways this will happen.

It would be a good idea to have this prequel affect some element you haven't expanded on so that there can be a sense of the unknown. Even though the unknown is not required for tension, it is a catalyst that makes tension stronger. Anything that increases the schism between what a reader wants and what they expect has the potential to increase tension.

This is often the reason so many prequels fail and I would caution you not to write one if you have another option at hand. If they're dealing with well known elements that lack of mystery does make it harder to write a lot of the little interceding bits.

A word of caution

If you piss off your readers, you don't get tension; you get bad reviews. There are obvious attempts to create tension that will instead piss readers off and send them running away. This is part of why writing is hard and everyone wants realistic, "good" writing.

Things to think about

Why does death, even though it is often expected, feel so tense?
Why does uncomfortable humor make you uncomfortable, even though you know so much about the situation?
If you know something bad will happen, what often accompanies that to make it more tense?
How do all those stories where people don't die, work?

---

(0)

Life and death is actually a pretty low-stakes conflict in my opinion. Yes, of course, it's the ultimate thing we all want to avoid, but when it comes down to it, how many of us have experienced being dead?

That's right: No-one. If you have, then get back into the grave, unholy zombie.

Amadeus brings up a good point about tension coming from the reader being curious about what comes next rather than the end result, but it's also worth noting that there are so many different kinds of stakes in a story involving warfare.

Instead of 'will MC survive', it could be 'will MC have to grieve her friends' deaths' (something more people have experience of), 'will MC lose their home', 'will MC ever psychologically recover from the cold hand of war', et cetera, et cetera. These are all things people have actually gone through and the consequences of which can be richly explored, far more than being dead ever could.

There are so many sources of tension; life or death is really just a go-to 'all or nothing' variant on it.

---

(0)

Tension is caused by reader's wanting to know "what happens next".
The MC survives in nearly every novel, in fact the MC dies so infrequently that people don't like those novels. They assume your MC will survive.
Tension is created by situations in which the reader isn't sure what is going to happen, the solution to whatever dilemma is happening on page 50 is not obvious. Say the house is on fire and the MC is trapped. It is only page 50, we know the MC will survive, we can even know that this situation will be resolved in the next 5 or 10 pages, we just aren't sure how the MC will survive, so we keep turning the pages.
If you watch the movie "Die Hard", you never doubt for a second that Bruce Willis is going to live through his ordeal and prevail. The same thing for "Taken", or 007: James Bond will never die in Bond flick. Neither will Harry Potter, or the MC of any detective series. Sherlock is not going to die.
Personal death isn't the only thing the MC has to fear; they can fear pain, imprisonment, torture (that doesn't have to leave any marks; e.g. most people don't know if you have broken an arm or leg in the distant past), injury like being shot or stabbed.
They can also fear the death of friends and loved ones, of children, of innocent strangers (all of which you can put in jeopardy, or even kill).
They can also fear failure, just because somebody lived doesn't mean they succeeded in their previous mission.
The audience can know the MC will live. The audience can know the MC will succeed (e.g. 007, Jason Bourne, nearly any detective series, every Romantic Comedy has a happy ending).
Obviously, that is not where the tension comes from. It comes from the audience not knowing what happens next, and always having an open question in their mind about how some situation is going to turn out. It shouldn't always be the same question throughout the novel, it can and should be a long series of steps in solving the main question, some of them with failures and setbacks along the way. Readers will become numb and bored by success if it seems guaranteed. A mix of failure and success keeps them guessing, and what they are guessing about is "how THIS situation" turns out or is overcome: There is your tension, even if the final results are known.

---

(0)