Crafting & Combination

Arx is famous for baking bread, and there is no bread recipe anywhere in the game. There is an item that knows what to become when you touch water to it.

The primitive

Every "recipe" is an ON COMBINE handler on one of the two items, matching the other by class:

ON COMBINE {
  IF (^$PARAM1 ISCLASS "BOTTLE_WATER") {
    SENDEVENT CUSTOM ^$PARAM1 "EMPTY"     // consume or empty the reagent
    REPLACEME "\provisions\bread_uncooked\bread_uncooked"
  }
}

REPLACEME swaps the entity for a different one. That is the whole system: items do not have recipes, they have transformations. No recipe book, no crafting menu, no skill check, no failure state. The knowledge lives in the world and in the player's head.

The verified bread chain

Step	Inputs	Result
1	Flour + bottle of water (bottle emptied, not destroyed)	Uncooked bread
2	Uncooked bread + rolling pin	Uncooked pie base
3a	Pie base + shredded meat (consumed)	Uncooked meat pie
3b	Pie base + apple or carrot (consumed)	Uncooked apple pie
4	Any uncooked pie + bottle of wine (consumed)	Wine variant
5	Place on a heat source, wait 5 s	Cooked bread / pie / apple pie

A parallel chain exists for meat: food prep + salt makes an iron ration; + garlic, wine, or oil flavours it (the item keeps its identity but changes name, icon and skin and sets an enchanted flag, so it cooks into the garlic variant instead).

Prices climb through the chain — flour 2, pie base 5, food prep 8, uncooked apple pie 20 — so cooking is also the one genuine value-adding activity in an economy that otherwise only leaks.

Every ON COOK handler opens with the same guard:

IF (^INPLAYERINVENTORY == 1) ACCEPT      // do nothing

Food will not cook while you are carrying it. You have to drop it on the fire. This is the same rule as the pillar puzzle that refuses a stone you are still holding — the simulation insists that placement is different from possession, consistently, across systems that share nothing else.

While cooking, a timer increments the object's scale every 50–100 ms, so the dough visibly swells in the fire before the 5-second swap fires. No progress bar; the feedback is the object itself. That is a one-line trick doing the work of a UI.

Small details that carry weight

Eating raw flour triggers SPECIALFX HEAL -2 — it hurts you. The game answers a stupid experiment rather than blocking it.
Uncooked food refuses to be eaten with a spoken line rather than a grey-out.
Carrot and apple produce the same apple pie. The recipe space is loose, not a lookup table.
Items carry SET_STEAL (pickpocket difficulty, typically 50), PLAYERSTACKSIZE, SET_PRICE and SET_WEIGHT — and weight is almost always 0 or 1, confirming Arx has no meaningful encumbrance economy.

Design reading

The strength: because combination is just an event on an entity, anything can be combinable with anything, including quest items, tools, and objects the designer thought of five minutes before shipping. There is no system to extend — you write a handler. That is why Arx has cooking, dyeing, flavouring, tool use and puzzle assembly with no shared machinery, and why the affordances feel unbounded.

The cost: discovery is entirely unaided. Nothing tells you flour plus water is anything; the chain is transmitted by NPC dialogue, a note, or word of mouth outside the game. Combinations that were never authored fail silently and identically to combinations you got wrong, so the player cannot distinguish "not a recipe" from "wrong order". A modern version would keep the architecture and add one thing: a distinct response for plausible but unauthored combinations.

And it is fragile in the same way everything else here is: reagents are consumed and the world is persistent, so a chain begun with the only apple on the level is a chain you can lose.

Touchpoints

→ Simulation & Interaction: COMBINE and REPLACEME are the same verbs the rest of the world runs on
→ Puzzles & Traps: identical primitives, applied to level design instead of food
→ Economy & Items: cooking is the only value-adding transformation in the economy
→ Core Loop: hunger is the reason any of this matters

What breaks if you remove it

The fortress stops feeling inhabited. Cooking is not a mechanic Arx needs — it is the evidence that the world obeys rules beyond combat, and it is the single most-remembered thing about the game after the runes.