From revisions made to the design of the online simulation game Dwarf Fortress since its inception in 2006.
Stopped children from joining adventures.
Stopped soldiers from going to parties.
Stopped elves from being pleased with unethical trades.
Stopped dwarves from targeting harmless insane people.
Made thieves and their support groups respect each other.
Made semi-megabeasts get along better with their cave friends.
Made all undead respectful of one another.
Made dwarves care if you melt down their masterpieces.