World and lore
How to Set World Rules and Lore Your AI Will Not Break
Turn the rules of your world into rules in a model and have a checker walk every path. It shows the exact scenes where a new item breaks your world.
World State Flags
One shared memory lets any part of the game react to what the player did, without the parts knowing about each other, so choices and progress can change the world in many places at once.
Lore Codex
A codex gives the story a place to live outside the action. The player collects it at their own pace, sees how much is still missing, and comes back to a half-understood mystery later.
Stop a desert from touching a frozen land and work out the buffer between
A world drawn from separate ideas ends up with sand dunes right beside a snowfield, and the lore has no way to explain it. Here is how to list which landscapes may touch, find every bad border on the map, and learn which landscapes have to lie between them.
Regrow a picked bush after the player returns, with no growth in winter
The berry bush across the valley is not loaded while the player is away, so it either stays bare for ever or is ripe the moment they pass. Here is how to work out, on arrival, how far it has grown from the days that passed, without growth in the cold months.
Check that a town in your world can feed itself through the winter
A mountain city of five thousand with three small fields sounds grand until someone asks what they eat in winter. Here is a season-by-season count of harvest, storage and hunger that finds the first season a settlement starves and how many fields it would need.
Scatter treasure over a map without hiding any in sealed pockets
A random scatter happily puts a chest in a cave the player can never enter, or three chests on one doorstep. Here is a placement that only uses ground the player can really reach, keeps chests apart, and tells you honestly when there is not enough room.
Show world codex entries only as far as the player has learned them
A codex that lists the villain's true name the moment the player first hears of him gives away the story. Write each entry in pieces that unlock separately, hide the rest, and find pieces nothing in the game can ever unlock.
Check that "north of the lake" is really north on your map
Dialogue and notes say the mine lies north of the village, while the map has it to the south-east, and the player with the map in hand loses trust. Here is a check that compares such sentences with the true positions, tells what the compass word should have been, and avoids the up-and-down trap of screen maps.
Draw borders between realms with a named zone where both have a claim
A sharp line halfway between two capitals makes the stronger realm look weak and gives no room for a border war. Here is how to let strength pull the line toward the weaker side, mark the cells too close to call, and keep the result the same however the cells are visited.
Find predators whose hunting grounds overlap more than the lore allows
Two packs that each rule the same valley cannot both be telling the truth, but a pair of rivals touching at the edge is just good drama. Here is how to measure how much of the smaller territory the other one covers, and to let pairs that are meant to share do so.
Make sure exchanging coins around the world cannot create money
If three kingdoms each have their own coin and the rates are set one by one, a clever player can trade around in a circle and end with more than they started. Here is how to find such a loop and what fee closes it.