I try to fully outline my stories from beginning to end before I begin the writing proper.
I really enjoy world-building and my stories are very character-driven. I know who they are, what they want, what they are likely to do in any given situation and why they would behave that way. My problem is that I need some external impetus for them to respond to and for the life of me I can’t always think of a realistic or compelling one to keep the plot moving.
For example, my novel is set in a fantasy realm where most of the world is ruled by a single dominant empire that’s run by three fully intelligent undead. The tech level is equivalent to Steampunk or WW1 Europe but there is a single very powerful source of magic that forms the basis of the Empire’s power.
Society is rigidly hierarchical, with a few thousand similarly intelligent undead forming the Aristocracy. Think Zombies in Victorian frock coats with top hats and canes…
Anyway, regular humans form the vast underclass and in-between the two lie the “half-dead”. Despite the name, the half-dead are fully human and alive, but imbued with longer life, greater strength, speed and health than regular humans. Half-dead are created when a normal human has proven particularly valuable or useful to an Aristocratic master, so they normally perform the roles of trusted servants, bodyguards, elite soldiers and the like.
Amidst all of this, the human protagonist is travelling on a train to deliver an important item to so-and-so, but he is robbed by an agent of the antagonist. Figuring out what happens next is worryingly difficult. Does the protagonist return to his point of origin, or does he continue on to the person he was due to deliver the item to and report his failure? It’s bloody frustrating!