Slaves to Armok: God of Blood
Chapter II: Dwarf Fortress
Dwarf Fortress is a procedurally generated game made by brothers Tarn and Zach Adams released in 2006. Development is supported by crowdsourced donations. To play, the player needs to generate a new world through parameters ranging from resources to the length of the world's history. I imagine that the algorithm used to generate the world runs during the duration of the game. It likely randomly generates an elevation then picks areas to have biomes, then randomly picks what lives there and so on.
Graphics are simple text symbols, but they can be replaced with custom tilesets.
I admire the potential immersion that a player, they can literally do anything! The brothers' love for generating random worlds is visible.
The effective complexity of this piece is closer to disorder because the game world is constantly changing due to random events
The video that introduced me to Dwarf Fortress (view at your own discretion NSFW):