Random events: earthquakes, overflowing rivers, new gold veins (free games and versus, can be switched off)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/ROADMAP.md

@@ -73,7 +73,10 @@ bosses (`src/bosses.rs`: four champions of the Order lead every fifth wave - Sir
 Dame Seraphine's radiant burst, Brother Halvard's call to arms, Captain Rothgar's charge - with a health bar
 and loot), statistics (`src/stats.rs`: counters and a chart at the end of a game) and achievements
 (`src/achievements.rs`: 64 of them, kept in the browser and merged with `/api/profile` on the server after a
-login; the menu page *Achievements*). Room levels 2 and 3 will be researched in the library (per room kind).
+login; the menu page *Achievements*), room levels 2 and 3 (researched in the library once every tool is known:
++25% per level, brighter, gold trim) and random events (`src/events.rs`: earthquake, lava or water over the
+banks, a new gold vein; every 8-12 minutes in free games and versus matches, switch in the game settings; the
+host's choice goes to every client with `"events"` in the create message).
 
 1. **Random events** – earthquake (tunnels cave in), lava eruption, flood, gold vein found. Rare
    (every 8–12 minutes), free play and multiplayer only, can be switched off in the menu; in

lang/cs.lang

@@ -246,6 +246,7 @@ set.lights = Zdroje světla
 set.ui_scale = Velikost rozhraní
 set.game_speed = Rychlost hry
 set.hints = Rady
+set.events = Náhodné události
 set.keys_hint = Klikni na akci a stiskni klávesu. Už použité klávesy se prohodí.
 set.press_key = Stiskni klávesu pro: {0}
 set.esc_cancel = Esc ruší
@@ -340,6 +341,10 @@ info.tortured = mučen
 info.prison = Zajatci: {0}/{1}
 
 msg.wave_warn_dir = Zvědové hlásí: vlna hrdinů {0} dorazí k bráně za 30 sekund! Chtějí vtrhnout ze směru: {1}.
+msg.event_quake = Zemětřesení! Tunely na {0} se zřítily.
+msg.event_lava = Láva se vylévá z břehů na {0}!
+msg.event_flood = Povodeň! Řeka se vylévá z břehů na {0}.
+msg.event_vein = Skřítci hlásí novou zlatou žílu na {0}!
 msg.wave_warn_two = Zvědové hlásí: vlna hrdinů {0} dorazí k bráně za 30 sekund! Rozdělí se a vtrhnou ze směrů: {1} a {2}.
 dir.n = sever
 dir.ne = severovýchod

lang/da.lang

@@ -246,6 +246,7 @@ set.lights = Lyskilder
 set.ui_scale = Brugerflade
 set.game_speed = Spilhastighed
 set.hints = Tips
+set.events = Tilfældige hændelser
 set.keys_hint = Klik på en handling og tryk på en tast. Taster der allerede er i brug, byttes om.
 set.press_key = Tryk på en tast for: {0}
 set.esc_cancel = Esc annullerer
@@ -339,6 +340,10 @@ info.carried = bæres til torturkammeret
 info.tortured = bliver tortureret
 info.prison = Fanger: {0}/{1}
 msg.wave_warn_dir = Spejderne melder: heltebølge {0} når porten om 30 sekunder! De vil bryde ind fra {1}.
+msg.event_quake = Jordskælv! Tunneller mod {0} er styrtet sammen.
+msg.event_lava = Lavaen går over sine bredder mod {0}!
+msg.event_flood = Oversvømmelse! Floden går over sine bredder mod {0}.
+msg.event_vein = Imps'ene melder om en ny guldåre mod {0}!
 msg.wave_warn_two = Spejderne melder: heltebølge {0} når porten om 30 sekunder! De deler sig og bryder ind fra {1} og {2}.
 dir.n = nord
 dir.ne = nordøst

lang/de.lang

@@ -245,6 +245,7 @@ set.lights = Lichtquellen
 set.ui_scale = Oberflächengröße
 set.game_speed = Spieltempo
 set.hints = Hinweise
+set.events = Zufallsereignisse
 set.keys_hint = Aktion anklicken und Taste drücken. Bereits belegte Tasten werden getauscht.
 set.press_key = Taste drücken für: {0}
 set.esc_cancel = Esc bricht ab
@@ -339,6 +340,10 @@ info.tortured = wird gefoltert
 info.prison = Gefangene: {0}/{1}
 
 msg.wave_warn_dir = Späher melden: Welle {0} erreicht in 30 Sekunden das Tor! Die Helden wollen von {1} einfallen.
+msg.event_quake = Erdbeben! Im {0} sind Gänge eingestürzt.
+msg.event_lava = Im {0} tritt die Lava über die Ufer!
+msg.event_flood = Hochwasser! Im {0} tritt der Fluss über die Ufer.
+msg.event_vein = Die Imps melden eine neue Goldader im {0}!
 msg.wave_warn_two = Späher melden: Welle {0} erreicht in 30 Sekunden das Tor! Die Helden teilen sich auf und fallen von {1} und von {2} ein.
 dir.n = Norden
 dir.ne = Nordosten

lang/el.lang

@@ -246,6 +246,7 @@ set.lights = Πηγές φωτός
 set.ui_scale = Μέγεθος διεπαφής
 set.game_speed = Ταχύτητα παιχνιδιού
 set.hints = Υποδείξεις
+set.events = Τυχαία γεγονότα
 set.keys_hint = Κάνε κλικ σε μια ενέργεια και πάτησε ένα πλήκτρο. Πλήκτρα που ήδη χρησιμοποιούνται ανταλλάσσονται.
 set.press_key = Πάτησε πλήκτρο για: {0}
 set.esc_cancel = Esc ακυρώνει
@@ -340,6 +341,10 @@ info.tortured = βασανίζεται
 info.prison = Αιχμάλωτοι: {0}/{1}
 
 msg.wave_warn_dir = Οι ανιχνευτές αναφέρουν: το κύμα ηρώων {0} φτάνει στην πύλη σε 30 δευτερόλεπτα! Σχεδιάζουν να εισβάλουν από: {1}.
+msg.event_quake = Σεισμός! Σήραγγες στα {0} κατέρρευσαν.
+msg.event_lava = Η λάβα ξεχειλίζει στα {0}!
+msg.event_flood = Πλημμύρα! Το ποτάμι ξεχειλίζει στα {0}.
+msg.event_vein = Τα διαβολάκια βρήκαν νέα φλέβα χρυσού στα {0}!
 msg.wave_warn_two = Οι ανιχνευτές αναφέρουν: το κύμα ηρώων {0} φτάνει στην πύλη σε 30 δευτερόλεπτα! Χωρίζονται και εισβάλλουν από: {1} και {2}.
 dir.n = βορρά
 dir.ne = βορειοανατολικά

lang/en.lang

@@ -246,6 +246,7 @@ set.lights = Light sources
 set.ui_scale = Interface size
 set.game_speed = Game speed
 set.hints = Hints
+set.events = Random events
 set.keys_hint = Click an action and press a key. Keys already in use are swapped.
 set.press_key = Press a key for: {0}
 set.esc_cancel = Esc cancels
@@ -340,6 +341,10 @@ info.tortured = being tortured
 info.prison = Prisoners: {0}/{1}
 
 msg.wave_warn_dir = Scouts report: hero wave {0} reaches the gate in 30 seconds! They plan to break in from the {1}.
+msg.event_quake = Earthquake! Tunnels in the {0} have caved in.
+msg.event_lava = The lava overflows its banks in the {0}!
+msg.event_flood = Flood! The river overflows its banks in the {0}.
+msg.event_vein = The imps report a new gold vein in the {0}!
 msg.wave_warn_two = Scouts report: hero wave {0} reaches the gate in 30 seconds! They split up and break in from the {1} and the {2}.
 dir.n = north
 dir.ne = north-east

lang/es.lang

@@ -246,6 +246,7 @@ set.lights = Fuentes de luz
 set.ui_scale = Tamaño de interfaz
 set.game_speed = Velocidad de juego
 set.hints = Consejos
+set.events = Sucesos aleatorios
 set.keys_hint = Haz clic en una acción y pulsa una tecla. Las teclas ya usadas se intercambian.
 set.press_key = Pulsa una tecla para: {0}
 set.esc_cancel = Esc cancela
@@ -340,6 +341,10 @@ info.tortured = siendo torturado
 info.prison = Prisioneros: {0}/{1}
 
 msg.wave_warn_dir = Los exploradores informan: ¡la oleada de héroes {0} llega a la puerta en 30 segundos! Planean entrar por el {1}.
+msg.event_quake = ¡Terremoto! Se han derrumbado túneles en el {0}.
+msg.event_lava = ¡La lava se desborda en el {0}!
+msg.event_flood = ¡Inundación! El río se desborda en el {0}.
+msg.event_vein = ¡Los diablillos informan de una nueva veta de oro en el {0}!
 msg.wave_warn_two = Los exploradores informan: ¡la oleada de héroes {0} llega a la puerta en 30 segundos! Se dividen y entran por el {1} y por el {2}.
 dir.n = norte
 dir.ne = nordeste

lang/fi.lang

@@ -246,6 +246,7 @@ set.lights = Valonlähteet
 set.ui_scale = UI-koko
 set.game_speed = Pelinopeus
 set.hints = Vinkit
+set.events = Satunnaiset tapahtumat
 set.keys_hint = Klikkaa toimintoa ja paina näppäintä. Jo käytössä olevat näppäimet vaihdetaan keskenään.
 set.press_key = Paina näppäintä toiminnolle: {0}
 set.esc_cancel = Esc peruu
@@ -340,6 +341,10 @@ info.tortured = kidutetaan
 info.prison = Vangit: {0}/{1}
 
 msg.wave_warn_dir = Tiedustelijat ilmoittavat: sankariaalto {0} saapuu portille 30 sekunnissa! Ne aikovat murtautua sisään suunnasta: {1}.
+msg.event_quake = Maanjäristys! Tunneleita on sortunut suunnassa {0}.
+msg.event_lava = Laava tulvii yli äyräidensä suunnassa {0}!
+msg.event_flood = Tulva! Joki tulvii yli äyräidensä suunnassa {0}.
+msg.event_vein = Pirut ilmoittavat uudesta kultasuonesta suunnassa {0}!
 msg.wave_warn_two = Tiedustelijat ilmoittavat: sankariaalto {0} saapuu portille 30 sekunnissa! Ne jakautuvat ja murtautuvat sisään suunnista: {1} ja {2}.
 dir.n = pohjoinen
 dir.ne = koillinen

lang/hr.lang

@@ -246,6 +246,7 @@ set.lights = Izvori svjetla
 set.ui_scale = Veličina sučelja
 set.game_speed = Brzina igre
 set.hints = Savjeti
+set.events = Slučajni događaji
 set.keys_hint = Klikni na radnju i pritisni tipku. Već zauzete tipke se zamijene.
 set.press_key = Pritisni tipku za: {0}
 set.esc_cancel = Esc poništava
@@ -340,6 +341,10 @@ info.tortured = muče ga
 info.prison = Zarobljenici: {0}/{1}
 
 msg.wave_warn_dir = Izviđači javljaju: val junaka {0} stiže do vrata za 30 sekundi! Planiraju provaliti sa strane: {1}.
+msg.event_quake = Potres! Tuneli na {0} su se urušili.
+msg.event_lava = Lava se izlijeva iz korita na {0}!
+msg.event_flood = Poplava! Rijeka se izlijeva na {0}.
+msg.event_vein = Vražići javljaju novu zlatnu žilu na {0}!
 msg.wave_warn_two = Izviđači javljaju: val junaka {0} stiže do vrata za 30 sekundi! Dijele se i provaljuju sa strana: {1} i {2}.
 dir.n = sjever
 dir.ne = sjeveroistok

lang/hu.lang

@@ -246,6 +246,7 @@ set.lights = Fényforrások
 set.ui_scale = Felület mérete
 set.game_speed = Játéksebesség
 set.hints = Tippek
+set.events = Véletlen események
 set.keys_hint = Kattints egy műveletre, és nyomj meg egy billentyűt. A már használt billentyűk felcserélődnek.
 set.press_key = Nyomj egy billentyűt ehhez: {0}
 set.esc_cancel = Esc: mégse
@@ -340,6 +341,10 @@ info.tortured = kínozzák
 info.prison = Foglyok: {0}/{1}
 
 msg.wave_warn_dir = A felderítők jelentik: a(z) {0}. hőshullám 30 másodperc múlva eléri a kaput! Innen akarnak betörni: {1}.
+msg.event_quake = Földrengés! Alagutak omlottak be: {0}.
+msg.event_lava = Kilép medréből a láva: {0}!
+msg.event_flood = Árvíz! Kilép medréből a folyó: {0}.
+msg.event_vein = A manók új aranyérre bukkantak: {0}!
 msg.wave_warn_two = A felderítők jelentik: a(z) {0}. hőshullám 30 másodperc múlva eléri a kaput! Kettéválnak, és két irányból törnek be: {1} és {2}.
 dir.n = észak
 dir.ne = északkelet

lang/it.lang

@@ -246,6 +246,7 @@ set.lights = Fonti di luce
 set.ui_scale = Dimensione interfaccia
 set.game_speed = Velocità di gioco
 set.hints = Suggerimenti
+set.events = Eventi casuali
 set.keys_hint = Clicca un'azione e premi un tasto. I tasti già in uso vengono scambiati.
 set.press_key = Premi un tasto per: {0}
 set.esc_cancel = Esc annulla
@@ -340,6 +341,10 @@ info.tortured = sotto tortura
 info.prison = Prigionieri: {0}/{1}
 
 msg.wave_warn_dir = Gli esploratori riferiscono: l'ondata di eroi {0} raggiunge la porta tra 30 secondi! Vogliono irrompere da {1}.
+msg.event_quake = Terremoto! Sono crollati dei tunnel a {0}.
+msg.event_lava = La lava straripa a {0}!
+msg.event_flood = Inondazione! Il fiume straripa a {0}.
+msg.event_vein = I diavoletti segnalano una nuova vena d'oro a {0}!
 msg.wave_warn_two = Gli esploratori riferiscono: l'ondata di eroi {0} raggiunge la porta tra 30 secondi! Si dividono e irrompono da {1} e da {2}.
 dir.n = nord
 dir.ne = nord-est

lang/nl.lang

@@ -246,6 +246,7 @@ set.lights = Lichtbronnen
 set.ui_scale = Interfacegrootte
 set.game_speed = Spelsnelheid
 set.hints = Tips
+set.events = Willekeurige gebeurtenissen
 set.keys_hint = Klik op een actie en druk op een toets. Toetsen die al in gebruik zijn, worden verwisseld.
 set.press_key = Druk op een toets voor: {0}
 set.esc_cancel = Esc annuleert
@@ -340,6 +341,10 @@ info.tortured = wordt gemarteld
 info.prison = Gevangenen: {0}/{1}
 
 msg.wave_warn_dir = Verkenners melden: heldengolf {0} bereikt de poort over 30 seconden! Ze willen vanuit het {1} binnenvallen.
+msg.event_quake = Aardbeving! Tunnels in het {0} zijn ingestort.
+msg.event_lava = De lava treedt buiten haar oevers in het {0}!
+msg.event_flood = Overstroming! De rivier treedt buiten haar oevers in het {0}.
+msg.event_vein = De duiveltjes melden een nieuwe goudader in het {0}!
 msg.wave_warn_two = Verkenners melden: heldengolf {0} bereikt de poort over 30 seconden! Ze splitsen zich en vallen binnen vanuit het {1} en het {2}.
 dir.n = noorden
 dir.ne = noordoosten

lang/no.lang

@@ -246,6 +246,7 @@ set.lights = Lyskilder
 set.ui_scale = Grensesnitt
 set.game_speed = Spillfart
 set.hints = Tips
+set.events = Tilfeldige hendelser
 set.keys_hint = Klikk på en handling og trykk på en tast. Taster som allerede er i bruk, byttes om.
 set.press_key = Trykk på en tast for: {0}
 set.esc_cancel = Esc avbryter
@@ -339,6 +340,10 @@ info.carried = bæres til torturkammeret
 info.tortured = blir torturert
 info.prison = Fanger: {0}/{1}
 msg.wave_warn_dir = Speiderne melder: heltebølge {0} når porten om 30 sekunder! De vil bryte inn fra {1}.
+msg.event_quake = Jordskjelv! Tunneler mot {0} har rast sammen.
+msg.event_lava = Lavaen går over sine bredder mot {0}!
+msg.event_flood = Flom! Elva går over sine bredder mot {0}.
+msg.event_vein = Impene melder om en ny gullåre mot {0}!
 msg.wave_warn_two = Speiderne melder: heltebølge {0} når porten om 30 sekunder! De deler seg og bryter inn fra {1} og {2}.
 dir.n = nord
 dir.ne = nordøst

lang/pt.lang

@@ -246,6 +246,7 @@ set.lights = Fontes de luz
 set.ui_scale = Tamanho da interface
 set.game_speed = Velocidade do jogo
 set.hints = Dicas
+set.events = Eventos aleatórios
 set.keys_hint = Clica numa ação e prime uma tecla. Teclas já em uso são trocadas.
 set.press_key = Prime uma tecla para: {0}
 set.esc_cancel = Esc cancela
@@ -340,6 +341,10 @@ info.tortured = a ser torturado
 info.prison = Prisioneiros: {0}/{1}
 
 msg.wave_warn_dir = Os batedores informam: a vaga de heróis {0} chega ao portão dentro de 30 segundos! Planeiam entrar pelo {1}.
+msg.event_quake = Terramoto! Desabaram túneis a {0}.
+msg.event_lava = A lava transborda a {0}!
+msg.event_flood = Cheia! O rio transborda a {0}.
+msg.event_vein = Os diabretes encontraram um novo veio de ouro a {0}!
 msg.wave_warn_two = Os batedores informam: a vaga de heróis {0} chega ao portão dentro de 30 segundos! Dividem-se e entram pelo {1} e pelo {2}.
 dir.n = norte
 dir.ne = nordeste

lang/ro.lang

@@ -246,6 +246,7 @@ set.lights = Surse de lumină
 set.ui_scale = Mărime interfață
 set.game_speed = Viteza jocului
 set.hints = Sfaturi
+set.events = Evenimente aleatorii
 set.keys_hint = Clic pe o acțiune și apasă o tastă. Tastele deja folosite se schimbă între ele.
 set.press_key = Apasă o tastă pentru: {0}
 set.esc_cancel = Esc anulează
@@ -340,6 +341,10 @@ info.tortured = e torturat
 info.prison = Prizonieri: {0}/{1}
 
 msg.wave_warn_dir = Iscoadele raportează: valul de eroi {0} ajunge la poartă în 30 de secunde! Plănuiesc să pătrundă dinspre {1}.
+msg.event_quake = Cutremur! S-au prăbușit tuneluri în {0}.
+msg.event_lava = Lava se revarsă în {0}!
+msg.event_flood = Inundație! Râul se revarsă în {0}.
+msg.event_vein = Drăcușorii au găsit un nou filon de aur în {0}!
 msg.wave_warn_two = Iscoadele raportează: valul de eroi {0} ajunge la poartă în 30 de secunde! Se despart și pătrund dinspre {1} și dinspre {2}.
 dir.n = nord
 dir.ne = nord-est

lang/ru.lang

@@ -246,6 +246,7 @@ set.lights = Источники света
 set.ui_scale = Размер интерфейса
 set.game_speed = Скорость игры
 set.hints = Подсказки
+set.events = Случайные события
 set.keys_hint = Выбери действие и нажми клавишу. Занятые клавиши меняются местами.
 set.press_key = Нажми клавишу для: {0}
 set.esc_cancel = Esc - отмена
@@ -340,6 +341,10 @@ info.tortured = его пытают
 info.prison = Пленники: {0}/{1}
 
 msg.wave_warn_dir = Разведчики докладывают: волна героев {0} будет у врат через 30 секунд! Они хотят прорваться с направления: {1}.
+msg.event_quake = Землетрясение! Туннели на {0} обрушились.
+msg.event_lava = Лава выходит из берегов на {0}!
+msg.event_flood = Наводнение! Река выходит из берегов на {0}.
+msg.event_vein = Бесы докладывают о новой золотой жиле на {0}!
 msg.wave_warn_two = Разведчики докладывают: волна героев {0} будет у врат через 30 секунд! Они разделились и прорвутся с направлений: {1} и {2}.
 dir.n = север
 dir.ne = северо-восток

lang/sk.lang

@@ -246,6 +246,7 @@ set.lights = Zdroje svetla
 set.ui_scale = Veľkosť rozhrania
 set.game_speed = Rýchlosť hry
 set.hints = Rady
+set.events = Náhodné udalosti
 set.keys_hint = Klikni na akciu a stlač kláves. Už použité klávesy sa vymenia.
 set.press_key = Stlač kláves pre: {0}
 set.esc_cancel = Esc ruší
@@ -340,6 +341,10 @@ info.tortured = mučený
 info.prison = Zajatci: {0}/{1}
 
 msg.wave_warn_dir = Zvedi hlásia: vlna hrdinov {0} dorazí k bráne o 30 sekúnd! Chcú vtrhnúť zo smeru: {1}.
+msg.event_quake = Zemetrasenie! Tunely na {0} sa zrútili.
+msg.event_lava = Láva sa vylieva z brehov na {0}!
+msg.event_flood = Povodeň! Rieka sa vylieva z brehov na {0}.
+msg.event_vein = Škriatkovia hlásia novú zlatú žilu na {0}!
 msg.wave_warn_two = Zvedi hlásia: vlna hrdinov {0} dorazí k bráne o 30 sekúnd! Rozdelia sa a vtrhnú zo smerov: {1} a {2}.
 dir.n = sever
 dir.ne = severovýchod

lang/sr.lang

@@ -246,6 +246,7 @@ set.lights = Извори светла
 set.ui_scale = Величина интерфејса
 set.game_speed = Брзина игре
 set.hints = Савети
+set.events = Случајни догађаји
 set.keys_hint = Кликни на радњу и притисни тастер. Већ заузети тастери се замене.
 set.press_key = Притисни тастер за: {0}
 set.esc_cancel = Esc поништава
@@ -340,6 +341,10 @@ info.tortured = муче га
 info.prison = Заробљеници: {0}/{1}
 
 msg.wave_warn_dir = Извиђачи јављају: талас хероја {0} стиже до капије за 30 секунди! Планирају да провале са стране: {1}.
+msg.event_quake = Земљотрес! Тунели на {0} су се урушили.
+msg.event_lava = Лава се излива из корита на {0}!
+msg.event_flood = Поплава! Река се излива на {0}.
+msg.event_vein = Врагови јављају нову златну жилу на {0}!
 msg.wave_warn_two = Извиђачи јављају: талас хероја {0} стиже до капије за 30 секунди! Деле се и проваљују са страна: {1} и {2}.
 dir.n = север
 dir.ne = североисток

lang/sv.lang

@@ -246,6 +246,7 @@ set.lights = Ljuskällor
 set.ui_scale = Gränssnittsstorlek
 set.game_speed = Spelhastighet
 set.hints = Tips
+set.events = Slumpmässiga händelser
 set.keys_hint = Klicka på en åtgärd och tryck på en tangent. Tangenter som redan används byter plats.
 set.press_key = Tryck på en tangent för: {0}
 set.esc_cancel = Esc avbryter
@@ -340,6 +341,10 @@ info.tortured = torteras
 info.prison = Fångar: {0}/{1}
 
 msg.wave_warn_dir = Spejarna rapporterar: hjältevåg {0} når porten om 30 sekunder! De tänker bryta sig in från {1}.
+msg.event_quake = Jordbävning! Tunnlar i {0} har rasat.
+msg.event_lava = Lavan svämmar över sina bräddar i {0}!
+msg.event_flood = Översvämning! Floden svämmar över i {0}.
+msg.event_vein = Imparna rapporterar en ny guldåder i {0}!
 msg.wave_warn_two = Spejarna rapporterar: hjältevåg {0} når porten om 30 sekunder! De delar upp sig och bryter in från {1} och {2}.
 dir.n = norr
 dir.ne = nordost

server/src/netplay.rs

@@ -90,6 +90,7 @@ struct Room {
     doc: Option<Value>, // editor campaign of a co-op match (sent to every client at the start)
     resume: Option<(u32, Value)>, // a resumed editor campaign run: its seed and what the masters carry
     surface: bool, // a free match half above ground
+    events: bool,  // random events in a free match
 }
 
 #[derive(Debug)]
@@ -384,7 +385,7 @@ impl Netplay {
         }
         let name = self.clients.get(&conn).map(|c| c.name.clone()).unwrap_or_else(|| "Guest".into());
         let seats = sides.iter().map(|s| (*s, new_seat(*s, false))).collect::<HashMap<_, _>>();
-        let room = Room { code: code.clone(), sides, seats, pending: HashMap::new(), turn: 0, started: false, paused: false, missing: false, seed: None, map_w, map_h, difficulty, mission, doc, resume, surface: msg.get("surface").and_then(|v| v.as_bool()).unwrap_or(false) };
+        let room = Room { code: code.clone(), sides, seats, pending: HashMap::new(), turn: 0, started: false, paused: false, missing: false, seed: None, map_w, map_h, difficulty, mission, doc, resume, surface: msg.get("surface").and_then(|v| v.as_bool()).unwrap_or(false), events: msg.get("events").and_then(|v| v.as_bool()).unwrap_or(false) };
         self.rooms.insert(code.clone(), room);
         if let Some(c) = self.clients.get_mut(&conn) {
             c.room = Some(code.clone());
@@ -652,6 +653,9 @@ impl Netplay {
                 if r.surface {
                     m["surface"] = json!(true);
                 }
+                if r.events {
+                    m["events"] = json!(true);
+                }
                 if let Some((_, carry)) = &r.resume {
                     m["carry"] = carry.clone();
                     m["resume"] = json!(true);

src/events.rs

@@ -0,0 +1,190 @@
+// Random events in free games and versus matches (rare; can be switched off): an earthquake
+// brings down tunnels near the dungeon, lava or water overflows its banks, or the imps find a
+// new gold vein. Shared state and the shared random numbers: every client of a match sees the
+// same. Campaigns have none (their stories are told by the missions).
+
+use crate::game::*;
+use crate::map::*;
+use serde::{Deserialize, Serialize};
+
+// seconds between two events: EVENT_GAP plus up to EVENT_SPREAD
+pub const EVENT_GAP: f32 = 480.0;
+pub const EVENT_SPREAD: f32 = 240.0;
+
+#[derive(Clone, Debug, Default, Serialize, Deserialize)]
+pub struct Events {
+    pub t: f32, // seconds until the next one
+}
+
+impl Game {
+    // switches random events on (new free game or match) or off
+    pub fn set_events(&mut self, on: bool) {
+        self.happenings = if on && self.mission.is_none() { Some(Events { t: EVENT_GAP + self.rng.f() * EVENT_SPREAD }) } else { None };
+    }
+
+    pub(crate) fn update_events(&mut self, dt: f32) {
+        let Some(ev) = self.happenings.as_mut() else { return };
+        ev.t -= dt;
+        if ev.t > 0.0 {
+            return;
+        }
+        ev.t = EVENT_GAP + self.rng.f() * EVENT_SPREAD;
+        let kind = self.rng.next() % 4;
+        let happened = match kind {
+            0 => self.event_quake(),
+            1 => self.event_overflow(Kind::Lava),
+            2 => self.event_overflow(Kind::Water),
+            _ => self.event_vein(),
+        };
+        // nothing of that kind possible here: a gold vein instead (there is always earth)
+        if !happened && kind != 3 {
+            self.event_vein();
+        }
+    }
+
+    // own walkable ground within `r` of tile i?
+    fn near_own(&self, i: usize, r: i32) -> bool {
+        let (x, y) = xy(i);
+        (-r..=r).any(|dy| (-r..=r).any(|dx| self.map.get(x + dx, y + dy).map_or(false, |t| t.owner != Owner::None && t.owner != Owner::Hero && t.walkable())))
+    }
+
+    fn announce(&mut self, key: &'static str, i: usize) {
+        let (x, y) = xy(i);
+        let dir = format!("@{}", self.direction_key((x, y)));
+        // every master hears of it
+        let me = self.me_side;
+        for s in self.master_sides() {
+            self.switch_to(s);
+            self.msg(key, vec![dir.clone()]);
+            self.sfx_ui(Sfx::CoreHit);
+        }
+        self.switch_to(me);
+        self.add_mark(x as f32 + 0.5, y as f32 + 0.5, crate::game::MARK_BRIDGE, 255, 8.0, true);
+    }
+
+    // an earthquake: plain tunnels (unowned, not rooms) near a dungeon cave in
+    fn event_quake(&mut self) -> bool {
+        let n = self.map.t.len();
+        let cands: Vec<usize> = (0..n).filter(|&i| {
+            let t = &self.map.t[i];
+            let (x, y) = xy(i);
+            t.kind == Kind::Floor && t.owner == Owner::None && x > 2 && y > 2 && x < mw() as i32 - 3 && y < mh() as i32 - 3 && !self.map.sky(i) && self.near_own(i, 6)
+        }).collect();
+        if cands.len() < 4 {
+            return false;
+        }
+        let centre = cands[(self.rng.next() as usize) % cands.len()];
+        let (cx, cy) = xy(centre);
+        let mut fell = 0;
+        for &i in &cands {
+            let (x, y) = xy(i);
+            if (x - cx).abs() + (y - cy).abs() > 3 || self.rng.f() < 0.35 {
+                continue;
+            }
+            if self.ents.iter().any(|e| e.alive && e.tile() == i) {
+                continue; // nobody is buried alive (the quake is not that mean)
+            }
+            let t = &mut self.map.t[i];
+            t.kind = Kind::Earth;
+            t.hp = 6.0;
+            t.marked = false;
+            fell += 1;
+        }
+        if fell == 0 {
+            return false;
+        }
+        self.announce("msg.event_quake", centre);
+        true
+    }
+
+    // a river overflows its banks: unowned open ground next to it fills
+    fn event_overflow(&mut self, river: Kind) -> bool {
+        let n = self.map.t.len();
+        let bank: Vec<usize> = (0..n).filter(|&i| {
+            let t = &self.map.t[i];
+            let (x, y) = xy(i);
+            // no lava above ground
+            t.kind == Kind::Floor && t.owner == Owner::None && !(river == Kind::Lava && self.map.sky(i))
+                && DIR4.iter().any(|&(dx, dy)| self.map.get(x + dx, y + dy).map_or(false, |o| o.kind == river))
+        }).collect();
+        if bank.is_empty() {
+            return false;
+        }
+        let start = bank[(self.rng.next() as usize) % bank.len()];
+        let (sx, sy) = xy(start);
+        let mut done = 0;
+        for &i in &bank {
+            let (x, y) = xy(i);
+            if (x - sx).abs() + (y - sy).abs() > 4 || done >= 8 {
+                continue;
+            }
+            self.map.t[i].kind = river;
+            self.ground_lost(i);
+            done += 1;
+        }
+        self.announce(if river == Kind::Lava { "msg.event_lava" } else { "msg.event_flood" }, start);
+        true
+    }
+
+    // the imps find a gold vein: earth near a dungeon turns to gold
+    fn event_vein(&mut self) -> bool {
+        let n = self.map.t.len();
+        let cands: Vec<usize> = (0..n).filter(|&i| self.map.t[i].kind == Kind::Earth && !self.map.t[i].reinforced && self.near_own(i, 5)).collect();
+        if cands.is_empty() {
+            return false;
+        }
+        let centre = cands[(self.rng.next() as usize) % cands.len()];
+        let (cx, cy) = xy(centre);
+        for &i in &cands {
+            let (x, y) = xy(i);
+            if (x - cx).abs() + (y - cy).abs() <= 2 {
+                let t = &mut self.map.t[i];
+                t.kind = Kind::Gold;
+                t.gold = 900;
+            }
+        }
+        self.announce("msg.event_vein", centre);
+        true
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn free_games_have_rare_events() {
+        let mut g = Game::new(12, 80, 64);
+        g.set_events(true);
+        assert!(g.happenings.is_some());
+        let golds = |g: &Game| g.map.t.iter().filter(|t| t.kind == Kind::Gold).count();
+        let before = golds(&g);
+        g.happenings.as_mut().unwrap().t = 0.0;
+        g.rng = Rng(3); // a gold vein (or another event) happens now
+        g.update_events(0.1);
+        assert!(g.happenings.as_ref().unwrap().t >= EVENT_GAP);
+        assert!(g.msgs.iter().any(|m| m.key.starts_with("msg.event_")), "an event was told");
+        let _ = before;
+        // campaigns have none
+        let mut m = crate::campaign::start_mission(3, None);
+        m.set_events(true);
+        assert!(m.happenings.is_none());
+    }
+
+    #[test]
+    fn every_event_can_happen() {
+        let mut g = Game::new(12, 80, 64);
+        let (cx, cy) = g.map.core;
+        // a little lava and water next to unowned ground near the dungeon
+        for (x, k) in [(cx + 6, Kind::Lava), (cx + 9, Kind::Water)] {
+            for y in cy - 2..cy + 3 {
+                g.map.t[idx(x, y)].kind = k;
+                g.map.t[idx(x + 1, y)].kind = Kind::Floor;
+                g.map.t[idx(x + 1, y)].owner = Owner::None;
+            }
+        }
+        assert!(g.event_vein());
+        assert!(g.event_overflow(Kind::Lava));
+        assert!(g.event_overflow(Kind::Water));
+    }
+}

src/game.rs

@@ -604,6 +604,8 @@ pub struct Game {
     #[serde(default)]
     pub bridgework: crate::bridges::BridgeWork, // burning and worn bridges
     #[serde(default)]
+    pub happenings: Option<crate::events::Events>, // random events (free games and versus), see events.rs
+    #[serde(default)]
     pub stats: crate::stats::GameStats, // statistics of the master at this computer (see stats.rs)
     #[serde(default)]
     pub wall_plans: Vec<(usize, u8)>, // walls to raise: tile, master side (see walls.rs)
@@ -943,6 +945,7 @@ impl Game {
             vrng: crate::particles::vrng(),
             dwarf_caves: Vec::new(),
             bridgework: Default::default(),
+            happenings: None,
             stats: Default::default(),
             wall_plans: Vec::new(),
             wood: crate::wood::WOOD_START,
@@ -1715,6 +1718,7 @@ impl Game {
         self.update_dwarves(dt);
         self.update_bridges(dt);
         self.update_wood(dt);
+        self.update_events(dt);
         // fallen hearts of a match are shared state: every client marks them in the same step
         self.update_fallen_masters();
         // the end of the game and the fog are about the master at this computer

src/lobby.rs

@@ -91,6 +91,7 @@ pub struct StartInfo {
     pub next: bool, // the next mission of a running editor campaign co-op match
     pub carry: Vec<(u8, crate::campaign::Carry)>, // what every side brings into that mission
     pub surface: bool, // a free match whose eastern half lies above ground
+    pub events: bool,  // random events in a free match
 }
 
 #[derive(Clone, Debug, Default)]
@@ -225,12 +226,13 @@ impl MatchClient {
     }
 
     // a free match; `surface`: its eastern half lies above ground
-    pub fn create_land(&mut self, sides: &[u8], map_w: usize, map_h: usize, difficulty: u8, surface: bool) {
+    pub fn create_land(&mut self, sides: &[u8], map_w: usize, map_h: usize, difficulty: u8, surface: bool, events: bool) {
         let n = self.outbox.len();
         self.send_create(sides, map_w, map_h, difficulty, None);
-        if let (true, Some(text)) = (surface, self.outbox.get_mut(n)) {
+        if let (true, Some(text)) = (surface || events, self.outbox.get_mut(n)) {
             if let Ok(mut msg) = serde_json::from_str::<Value>(text) {
-                msg["surface"] = json!(true);
+                msg["surface"] = json!(surface);
+                msg["events"] = json!(events);
                 *text = msg.to_string();
             }
         }
@@ -564,7 +566,8 @@ impl MatchClient {
         let resume = editor && v.get("resume").and_then(|x| x.as_bool()).unwrap_or(false);
         let carry: Vec<(u8, crate::campaign::Carry)> = if resume { v.get("carry").cloned().and_then(|c| serde_json::from_value(c).ok()).unwrap_or_default() } else { Vec::new() };
         let surface = v.get("surface").and_then(|x| x.as_bool()).unwrap_or(false);
-        self.start = Some(StartInfo { seed, map_w, map_h, difficulty, sides, local_side, mission, ai, doc, editor, teams, next: resume, carry, surface });
+        let events = v.get("events").and_then(|x| x.as_bool()).unwrap_or(false);
+        self.start = Some(StartInfo { seed, map_w, map_h, difficulty, sides, local_side, mission, ai, doc, editor, teams, next: resume, carry, surface, events });
         self.error = None;
         self.status = None;
     }
@@ -595,7 +598,7 @@ impl MatchClient {
             }
             r.ai = ai.clone();
         }
-        self.start = Some(StartInfo { seed, map_w, map_h, difficulty, sides, local_side, mission: Some(mission), ai, doc: Some(doc), editor: true, teams, next: true, carry, surface: false });
+        self.start = Some(StartInfo { seed, map_w, map_h, difficulty, sides, local_side, mission: Some(mission), ai, doc: Some(doc), editor: true, teams, next: true, carry, surface: false, events: false });
         self.error = None;
     }
 

src/main.rs

@@ -8,6 +8,7 @@ mod cloud;
 mod commands;
 mod demo;
 mod editor;
+mod events;
 mod dwarves;
 mod fog;
 mod fortress;
@@ -185,6 +186,7 @@ fn new_game(seed: u32, s: &Settings) -> (Game, Cam) {
         g.add_surface(seed, 0.5, 2 + (s.map_h / 64) as u32);
         g.init_fog();
     }
+    g.set_events(s.events);
     let (cx, cy) = g.map.core;
     let cam = Cam::new(cx as f32 + 1.5, cy as f32 + 1.5);
     (g, cam)
@@ -352,7 +354,7 @@ fn account_action(a: MenuAction, cloud: &mut Cloud, menu: &mut Menu, app: &mut A
             }
         }
         MenuAction::MatchJoin(code) => app.client.join(&code),
-        MenuAction::MatchCreate => app.client.create_land(&[0, 2, 3, 4], app.settings.map_w, app.settings.map_h, app.settings.difficulty, app.settings.surface),
+        MenuAction::MatchCreate => app.client.create_land(&[0, 2, 3, 4], app.settings.map_w, app.settings.map_h, app.settings.difficulty, app.settings.surface, app.settings.events),
         MenuAction::MatchCoopCreate(mission) => {
             let all = campaign::missions();
             if let Some(d) = all.get(mission) {
@@ -721,7 +723,7 @@ impl App {
         let next = run_seed.is_some();
         let seed = run_seed.unwrap_or_else(|| next_seed(self.seed));
         let editor = doc.is_some();
-        let info = StartInfo { seed, map_w, map_h, difficulty: self.settings.difficulty, sides: vec![0, 2], local_side: Some(0), mission: Some(mission), ai: vec![2], doc, editor, teams: Vec::new(), next, carry, surface: false };
+        let info = StartInfo { seed, map_w, map_h, difficulty: self.settings.difficulty, sides: vec![0, 2], local_side: Some(0), mission: Some(mission), ai: vec![2], doc, editor, teams: Vec::new(), next, carry, surface: false, events: false };
         if !self.start_match_game(info) {
             return false;
         }
@@ -805,6 +807,7 @@ impl App {
             // the same land on every client: built from the shared seed
             self.game.add_surface(info.seed, 0.5, 2 + (info.map_h / 64) as u32);
         }
+        self.game.set_events(info.events);
         self.game.coop = false;
         self.game.set_teams(&info.teams);
         self.game.ai_difficulty = info.difficulty;

src/menu.rs

@@ -64,6 +64,7 @@ pub enum Item {
     DebugPathLines,
     GameSpeed,
     Hints,
+    Events,
     TouchUi,
     Voice,
 }
@@ -74,7 +75,7 @@ fn tab_items(tab: usize) -> &'static [Item] {
         0 => &[Language, Volume, MusicVolume, Mute, Voice],
         1 => &[RotateSpeed, PanSpeed, ZoomSpeed, EdgeScroll, InvertMouse],
         2 => &[Outlines, WallDetail, Lights, UiScale, RenderScale],
-        3 => &[GameSpeed, Hints, TouchUi],
+        3 => &[GameSpeed, Hints, Events, TouchUi],
         4 => &[DebugFps, DebugFrameTime, DebugPing, DebugTriggerZones, DebugCommandMarkers, DebugPathLines],
         _ => &[],
     }
@@ -104,6 +105,7 @@ fn item_label(it: Item) -> String {
         Item::DebugPathLines => "set.debug_path_lines",
         Item::GameSpeed => "set.game_speed",
         Item::Hints => "set.hints",
+        Item::Events => "set.events",
         Item::TouchUi => "set.touch_ui",
         Item::Voice => "set.voice",
     })
@@ -160,6 +162,7 @@ fn item_value(it: Item, s: &Settings) -> String {
         }
         Item::GameSpeed => format!("{}x", s.game_speed as i32),
         Item::Hints => onoff(s.hints),
+        Item::Events => onoff(s.events),
         Item::TouchUi => match s.touch_ui {
             1 => tr("val.on"),
             2 => tr("val.off"),
@@ -207,6 +210,7 @@ fn item_change(it: Item, s: &mut Settings, d: i32) {
         Item::DebugPathLines => s.debug_path_lines = !s.debug_path_lines,
         Item::GameSpeed => s.game_speed = cycle(&[1.0f32, 2.0], s.game_speed, d),
         Item::Hints => s.hints = !s.hints,
+        Item::Events => s.events = !s.events,
         Item::TouchUi => s.touch_ui = cycle(&[0u8, 1, 2], s.touch_ui, d),
     }
 }

src/settings.rs

@@ -163,6 +163,7 @@ pub struct Settings {
     pub map_w: usize, // size of new maps (64..256)
     pub map_h: usize,
     pub surface: bool, // new free games: the eastern half lies above ground (forest)
+    pub events: bool,  // random events in free games and versus matches
     // key bindings: action id -> key name
     pub keys: BTreeMap<String, String>,
 }
@@ -198,6 +199,7 @@ impl Default for Settings {
             map_w: 64,
             map_h: 64,
             surface: false,
+            events: true,
             keys: BTreeMap::new(),
         }
     }