I just received an email notification stating that a mod had made alterations to this topic. Thank you for updating the current affected versions! I honestly haven’t tested since last time.
Originally, I came across this bug when I was making a mob farm. In my creative test world, using Slime Blocks to prevent mob spawning seemed to work, however, the opposite was true when I put it into practice on my survival world. A quick Google search yielded someone experiencing the same issue:
A little old, but still relevant. Addmitedly, I was quite salty at the time of creating this topic (considering that I’d spent hours building a Witch Farm). Now that Redstone prevents mob spawning, my initial concerns seem redundant. However, consistency is always nice, especially for mob farms that use Slime Blocks to spawn mobs!
Thanks all, cheers Mojang!
Okay, back up to date now, cheers!
I suddenly remembered that Minecraft comes with its own Java version now...
Still affects Minecraft 1.8.8 & 15w47c
I thought that I had completely deleted this world save, but it turns out that I hadn't! Here is a screenshot of my original example (in the latest snapshot) with it's seed displayed.
Okay, I appear to be unable to attach my world save folder to this, which makes sense, but I have included the seed in my screenshot.
Hi Alex! I know, that I'm back so soon, but I have rediscovered this issue in the latest snapshot! I really didn't think that I would. I will attach a new screenshot and proved a world download.
Hello Alex, I have updated the version to Minecraft 1.8 (as displayed in my latest screenshot). Unfortunately, I have recently deleted the world file that I had used for this occurrence. I really shouldn't have done so, and have not yet managed to successfully recreate the scenario. Neither did I provide a world download option for this particular world, for which I regret (or seed).
At the time of finding this bizarre "bug", I had made a Witch Farm design that used the Slime Block's inability (or so I thought) to allow mob spawning. I have recently remade my Witch Farm to utilize the new bounding box for Witch spawning in huts, so am honestly quite content at the moment!
If I ever rediscover this bug, I will be sure to report back, but until then - thank you for your time!
As Alec suggested, Slimes will not spawn within a Slime Chunk if it is above Y 39 (excluding Swamp Biomes), although this screenshot proves that it is indeed within the Slime spawning range.
Hi Kumasasa!
I too, have tried this. However, Slimes would not spawn in the day. I replaced the Slime Blocks with Stone to see if it made any difference, and still, no Slimes were spawned (attached picture).
*Edited because I spelled Kumasasa's name incorrectly. Note that Slimes would not spawn in the same world that I tested previously (the one with the water at night).
Have also tested in 1.13.1 - Created a Superflat world, one layer Bedrock and one layer Water. Made two Slime Block platforms. Instantly observed the attached result.
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