Mechanic · environment · city builder

Disasters

Events that destroy part of the player's city or base, set off by chance, by conditions, or by the player.

stubAlso: disaster, random disasters, natural disastersUpdated 2026-10-21
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Disasters damage a city by chance. In SimCity a roll each cycle sets one off, at odds that depend on the game level, and the monster comes only to a polluted city1.

  • SimCity (1989). A roll each cycle, 1 in 481 to 1 in 61 by level, then one of six disasters.1,2

See also

Lineage

Games

GameYearHowNote
SimCity1989a roll each cycle, 1 in 481 to 1 in 61 by level, then one of six disasters
Every claim about this mechanic, by game (2)
SimCity 1989Once per cycle, unless disasters are switched off (a switch added after the original release), a random disaster strikes with chance 1 in 481, 241, or 61 at game levels 0, 1, and 2. It is a fire or a flood with 2 chances in 9 each, a plane crash, tornado, or earthquake with 1 in 9 each, and with the last 2 in 9 a monster, but only if average pollution is above 60.Code
Each nuclear plant, on each cycle's visit and unless disasters are off, melts down with chance 1 in 30,001, 20,001, or 10,001 at game levels 0, 1, and 2.Code

References

  1. ^ abOnce per cycle, unless disasters are switched off (a switch added after the original release), a random disaster strikes with chance 1 in 481, 241, or 61 at game levels 0, 1, and 2. It is a fire or a flood with 2 chances in 9 each, a plane crash, tornado, or earthquake with 1 in 9 each, and with the last 2 in 9 a monster, but only if average pollution is above 60.CodeMicropolis (SimHacker/micropolis)revised
    How we know
    77  static short DisChance[3] = { 10*48, 5*48, 60};
    micropolis-activity/src/sim/s_disast.c lines 76–113 at c98f6b0 · upstream ↗
    1204  return (rnum % range);
    micropolis-activity/src/sim/s_sim.c lines 1195–1205 at c98f6b0 · upstream ↗

    Checked against the evidence by its author, an AI model, 2026-10-21.

    Revised after a check by a second AI model, 2026-10-21.

    In the claim ledger

  2. ^Each nuclear plant, on each cycle's visit and unless disasters are off, melts down with chance 1 in 30,001, 20,001, or 10,001 at game levels 0, 1, and 2.CodeMicropolis (SimHacker/micropolis)
    How we know
    1016  static short MltdwnTab[3] = { 30000, 20000, 10000 };  /* simadj */
    micropolis-activity/src/sim/s_sim.c line 1016 at c98f6b0 · upstream ↗
    1030    if (!NoDisasters && !Rand(MltdwnTab[GameLevel])) {
    micropolis-activity/src/sim/s_sim.c lines 1029–1033 at c98f6b0 · upstream ↗

    Checked against the evidence by its author, an AI model, 2026-10-21.

    Checked by a second AI model, 2026-10-21.

    In the claim ledger

Sources

Code