MC-42819 removes blaze spawners, which makes it impossible to beat the game, because there is no longer a way to get eyes of ender. The addition of villages makes it desirable for some players to turn off generated structures to make the gameplay more difficult. You could potentially save zombie villagers if blaze rods were still attainable somehow.
The inclusion of underground railways like the one at -45 : 21 : 27 (seed 1) clearly doesn't comply the remove-generated-structures rule, another feature that could potentially make game-play harder if removed and enhance gameplay for "hardcore" players.
The main issue is that "generate structures" is a nice feature to have if it does not make gameplay impossible.
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My mistake. It appears that rail mines and poisonous spider spawners (like the one mentioned in the description) are not generated. However, there are still other types of structures in the mines.
Steps to Reproduce:
Create a new creative mode world with "seed" 1
Make sure the "generated structures" option is off in "world" settings
Go to position 74 : -14 : 10
Observed Results:
There is a generated structure with a spawner
Expected Results:
I would not expect to see any generated structures in the mine
This duplicates MC-77787. Monster spawners are not structures, they're features just like geodes, fossils, or desert wells.
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