RareVillages makes villages much rarer, not by decreasing the chance of them spawning, but by increasing the space between them. You can use Jacobsjo's Minecraft Datapack Map to view the difference between Vanilla Minecraft and RareVillages.
Vanilla Villages:
- Without RareVillages, villages will spawn 34 chunks away from each other on average, with a minimum distance of just 8 chunks.
- With RareVillages V1 installed, villages will spawn 100 chunks away from each other on average, with a minimum distance of 50 chunks.
- With RareVillages V2 installed, villages will spawn 75 chunks away from each other on average, with a minimum distance of 34 chunks.
Please make sure you know which version you are downloading by checking the Versions page.
I have done some testing on Minecraft versions older than 1.21 and this datapack seems to work perfectly despite Minecraft saying that it's made for newer Minecraft versions. I havn't fully tested these versions yet so keep that in mind.
