Yellowstone Caldera Wonder

[King Phaedron]

3 Tile Passable Volcano: adds +1 culture to it's tiles normal yield. +1 Gold and +1 Science to adjacent tiles, which are subject to Volcanic soil and Eruption. Erupts infrequently and is usually not active. National Parks within 3 adjacent tiles provide double tourism.

Twice per game, during the Medieval Era, and Information or Future Era, it will create a Super Eruption that is likely to damage every single city and district on the continent the Wonder is found on, and pillage tile improvements. This event also causes all cities to produce double their faith generation that turn, as they feel validated in their religious zeal and driven to prostrate themselves in what is obviously the wrath of God. If the city has a Campus it will get double it's science output, as rational citizens are driven to investigate the disaster. All apostle Units on the continent at this time receive a free promotion.

 

[Alexander's Hetaroi]

This would be an Apocalypse mode only natural wonder right?

 

[Evie]

So far, the supereruptions we've been able to document were hundreds of thousands of years apart - the last one was 640000 years ago, before that 1.3 million years ago, before that 2.1 million years. The 6100 years the game last are a *drop in the water* in the kind of geological timescale Yellowstone operates on. It's very plausible that human civilization will rise, thrive, fall and vanish without ever witnessing a Yellowstone caldera eruption.

Having even a guaranteed one eruption in every game would be vast overkill ; having two in every game is purely asinine bonkerhood.

 

[Boris Gudenuf]

Since I live within sight (on a clear day) of a non-active but not dead volcano, some notes:

Violent Volcanic Eruptions are measured by the VEI (Volcanic Explosivity Index) similar to the Richter Scale for earthquake activity, each number on the scale is an Order of Magnitude greater than the one before, and the numbers measure amount of volcanic ash and rock ejected by the eruption - measured in cubic kilometers of matter.

So, VEI 5, for instance, ejects 1 cubic kilometer of matter, VEI 6 = 10, VEI 7 = 100.

The last VEI 8 (1000 cubic kilometers of ejecta) volcanic activity was about 27,000 years ago.

The last explosive Yellowstone explosive eruption was, as @Evie posted, about 640,000 years ago. The last Yellowstone volcanic activity besides hot water was about 70,000 years ago, and it was lava flow - no explosive activity at all.

Volcanic activity of a magnitude above VEI 7, in other words, has not occured within any time frame covered by the game, and continent-spanning volcanic ash and rock fall hasn't occured in the span of modern humanoids.

'Smaller' volcanic explosions are bad enough: the Vesuvian explosion that buried both Pompei and Herculanum in 79 CE was a VEI 5, for instance. - But 1 cubic kilometer of matter dumped all in one place has Really Bad local effects!

VEI 7, the largest that have occurred while us folks were on the planet, include:

Mount Mazama in 5680 BCE - that formed Crater Lake in Oregon, and deposited ash all the way up into Canada.

Thera north of Crete in 1628 BCE, that spread ash all the way to Egypt, crippled the Minoan civilization and ruined crops all over the eastern shores of the Mediterranean

Tambora in 1815 CE, that killed 20,000 people immediately and spewed so much volcanic ash and dust that it affected the world wide climate for the next year: 1816 was the 'Year Without Summer' in Europe.

There have only been 7 known VEI 7 explosions between 5680 BCE and the present day, to give you an idea of the frequency of Really Big volcanic actions - and 3 out of the 7 happened in relatively uninhabited paces like the Kamchatka Peninsula off northern Siberia or in Pre-city Japan (4300 BCE) or Argentina (2300 BCE). But anything over VEI 4 (the size of Mount Saint Helens in 1980, for an instance) can be considered at least locally catastrophic.

 

[Caesar of Bread]

3 Tile Passable Volcano: adds +1 culture to it's tiles normal yield. +1 Gold and +1 Science to adjacent tiles, which are subject to Volcanic soil and Eruption. Erupts infrequently and is usually not active. National Parks within 3 adjacent tiles provide double tourism.

Twice per game, during the Medieval Era, and Information or Future Era, it will create a Super Eruption that is likely to damage every single city and district on the continent the Wonder is found on, and pillage tile improvements. This event also causes all cities to produce double their faith generation that turn, as they feel validated in their religious zeal and driven to prostrate themselves in what is obviously the wrath of God. If the city has a Campus it will get double it's science output, as rational citizens are driven to investigate the disaster. All apostle Units on the continent at this time receive a free promotion.

Big volcano go kaboom

 

[GeneralZIft]

Starts off plausible then goes into bathorsehocky insane