Mob spawning on realms ignore light level.

Please attach screenshots that clearly show the lighting where the mobs are spawning.

Does the same problem happen in a downloaded copy of the world?

I have some screenshots here. Our realm is entirely lit and yet creepers seem to spawn still. I'm sorry I don't have any video footage of the issues. If anything happens again I will make sure to get some. This morning the issue happened again. It seems that creepers seem to spawn a lot, and we're not getting the same amount of spawns of skeletons/zombies. It makes it very stressful on my realm, especially since my little cousins are on and don't really know how to react when there are creepers spawning everywhere. I will make sure to update this post again if I get any more footage/screenshots. Here is some screenshots from my friend who keeps updating me on the issue.

In the screenshot showing the creeper it does appear that there is not enough lighting around where the creeper appears. Torches have a light level of 14, so if there are spawnable blocks more than 6 block moves away from a torch then mobs can spawn there.

I'm sorry but I will get a video showing you the world. I am on light 50%. There are lights absolutely everywhere. Plus, we are in a swamp biome which makes the ground look darker than it actually is.

Hey! I’ve been on this realm since the begining, it has been open for over a year and we have never had any issues with so many creepers until the current update. After the bee update we had a few but not to the extent of having an explosion every other day. Please please look into this further. We have tones of lanterns and torches around are area and shouldnt need to place one on every other block. Thank you 🙂

Hi! I've played on this realm through the previous updates and we notice a significant difference with the mob spawning. Examples such as creepers spawning in our well-lit houses without explanation are problems we haven't experienced until the latest version. Here's a clip that can possibly show some of what we're talking about and we find unusual because we haven't had these issues for the past year. The attached screenshot is the location up close that was in the clip. (we also have a lot of torches already set around our builds as well as inside)

I concur with @unknown that the picture with the creeper does not show light sources near enough to the creeper to prevent spawning in that area. I've also looked at the video provided by @unknown and marked the picture of the skeleton's spawn spot. Depending on which way is north, the skeleton spawned on the light level 7 block or the upper light level 6 block.

The reason you are getting these spawns now and did not in in previous versions of Minecraft is because 1.16 fixed the bug that allowed monsters to accumulate in hidden places and never despawn (MCPE-21856). It was common for the cave monster cap to be filled by monsters that spawned in hidden caves, and the surface monster cap to be filled by monsters from dungeon spawners or drowned in rivers and oceans. The chance of the caps filling would increase as you spent time in an area, for example building a base. With the new despawning system in 1.16, the hidden monsters are now able to despawn regularly, so new ones can spawn in other places. Monsters should now regularly respawn on full blocks in places you have already visited but have not fully lit.

There is also a separate bug in 1.16 that prevents zombies from spawning in caves, which explains why you seem to get proportionally more creepers indoors. (Note that the game's definition of "cave" is a coordinate that has a solid block somewhere above it, so this includes under a roof that contains solid blocks.)

When assessing your lighting, you may find it helpful to temporarily turn off smooth lighting (in video settings) to see how the light levels change block by block. For more information on calculating light levels see the Minecraft wiki.

This ticket will be resovled as a duplicate of MCPE-302.