Guardians are spawned in random places

Issue exists on my 1.8 server, chunks were originally generated in 1.7.9.
Seed: 26551365887039689
Coords: -333 32 -225

If seed is used in 1.8, a temple is present.

Although the Wiki says, "Ocean Monuments can spawn in existing chunks from older versions of Minecraft," it appears they do not, and only the Guardians spawn.

In my current world save, no monument spawned in an area I had previously explored, but I did find Guardians. So I loaded an older backup, in which that same area had not been previously explored, and found a monument.

It appears that monuments will NOT spawn in existing chunks, but the Guardians still do.

I encountered a similar problem. The Guardians are spawning in a River. But the World is generated in 1.8 and Amplified. When I try the same seed in a normal enviroment its still a river and no ocean nearby. (Seed: -4325619651631213966, coords: -319,y,291)

I encountered a similar problem. I created a new Single-player, Survival game on 1.8.1. I walked to a nice beach-y area, where I built my base and did all the playing. After a while, I started hearing strange noises which I couldn't identify (I hadn't been near Guardians yet). When I walked to the ocean the other day, I saw some guardians close to the surface. Because I couldn't see any monument around, I used "open to lan" in order to enable cheats, and flew there in creative mode, using a night vision potion to watch the water properly, and indeed there is no monument where I am standing, only a huge number of guardian mobs that immediately respawn if I use a /kill command.

The seed is 4354401103591561127. Coords are 301,74,-271. The save was created already on 1.8.1 and hasn't gone through any upgrade.

EDIT: I recreated the world in creative mode and teleported to the provided coords, and I can confirm that I do not see any monument, nor Guardians, in the area.

I don't know if this will be of use, but I used mcedit to make a copy of the save where only the affected area remains. I modified the spawn point and the player position to be close to the area where I have the issue.

Here is the link to the save: https://dl.dropboxusercontent.com/u/743491/Bug-Guardians.7z

@ David Quintana same situation, there are so many of them.

The issue lies in that the server is calculating DEEP_BIOME based on the 1.8 World Generator and NOT the worlds ACTUAL biome from previous versions.

I had a report of a biome in OCEAN (Not Deep), and when I generated a 1.8 world with exact same seed, sure enough that location was DEEP_OCEAN in that seed.

The Monument Structure check uses 2 different Biome lookup methods, and the one that does DEEP_BIOME check uses the World Gen calculations, and then the followup check for "Surrounding biomes" uses the actual worlds data.

I temp fixed for my server with the following change:

-       if (this.c.getWorldChunkManager().getBiome(new BlockPosition(k * 16 + 8, 64, l * 16 + 8), (BiomeBase) null) != BiomeBase.DEEP_OCEAN) {
+       if (!this.c.getWorldChunkManager().a(k * 16 + 8, l * 16 + 8, 16, Arrays.asList(BiomeBase.DEEP_OCEAN))) {

This issue has more flaws than this report states as it also causes monuments to spawn in the middle of Rivers, Frozen Rivers and Frozen Oceans, which is quite odd to stroll through the mountains and find a monument.

Like explain here : http://www.reddit.com/r/Minecraft/comments/2fco1f/is_it_possible_to_meet_guardians_without_an_ocean/

I have the same problem !

Happens in 1.8.8

Lets test with this code then 🙂

Happening in 15w46a. I didn't make a new world yet but the chunks they are spawning in were created before the bug started.

@unknown the fix only applies to newly generated chunks. Any created before 1.7, and visited during 1.8 with the bug will forever be marked as a water temple.

It just stops NEW cases of the bug.

A new world would not have this bug to begin with. It applies to pre 1.8 chunks being visited on 1.8+ worldgen.

But these chunks were spawned in 1.9 and initially they were not generating guardians. They have never been in 1.8.

edit: never mind, I see my mistake. Snapshots aren't really 1.9 in all regards.

Happening in 1.10.2 vanilla amplified. Prior to updating, when still in 1.9, no guardians in the ocean around my island. Since I updated to 1.10, there are two "ocean monuments" around my island, without the structures, but guardians spawn.

Please attach the world in its state before updating to 1.10.2.

Here's a world download. The guardians are spawning south-east of -1000x -240z. There were none before updating to 1.10. The world is amplified. http://bit.ly/29olW5v

Reopened pending further testing.

Is this still an issue in the most recent versions (currently that is 1.10.2, or 16w43a) of Minecraft? If so, please update the affected versions and help us keeping this ticket updated from time to time. If you are the owner/reporter of this ticket, you can modify the affected version(s) yourself.

It still is for me, in 1.10.2, in my LP world. I already attached a world download as it was in its state before updating to 1.10.2 in a previous comment.

with the nature of the bug, any chunk that loaded with the bug will be permanently 'bugged'.

The fix only applies to future chunk loads.

I gave Grum the fix to this bug, and it's still in place in 1.10.2.

To clarify more, the code says "is this block a monument" during structure generation.

These chunks loaded, and saved into the monument data file that there is a monument at that location when the logic for determining monuments was broken.

you would have to some how 'unprepare' the structures for that area and make it reprocess, which is not possible with vanilla tools/commands.

You mean that already generated chunks should be fixed ? That whould be quite complicated.