MCPE-105221Polar bears only spawn on ice
Polar bears only spawn on ice; they cannot spawn on snow or grass. This is makes it extremely rare to see them in snowy tundra biomes.
Steps to reproduce
- Open the test world, MCPE-105221 Polar Bear blocks.mcworld
. It consists of a 4-chunk spawn platform in a void frozen ocean world. Command blocks in front of the player switch the platform between snow, ice, and grass. Repeating command blocks Mark polar bear spawns with purple concrete and kill everything to keep the mob caps open. - Set the platform to snow.
- Wait a long time.
- Repeat steps 2-3 for ice and grass.
Expected result
Polar bears spawn on snow, ice, and grass, or at least in snow and ice.
Actual result
Polar bears only spawn on ice.
Linked Issues
MC-155496
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Created Issue:
Polar bears only spawn on ice
Polar bears only spawn on ice; they cannot spawn on snow or grass. This is makes it extremely rare to see them in snowy tundra biomes.
Steps to reproduce
- Open the test world. It consists of a 4-chunk spawn platform in a void frozen ocean world. Command blocks in front of the player switch the platform between snow, ice, and grass. Repeating command blocks Mark polar bear spawns with purple concrete and kill everything to keep the mob caps open.
- Set the platform to snow.
- Wait a long time.
- Repeat steps 2-3 for ice and grass.
Expected result
Polar bears spawn on snow, ice, and grass, or at least in snow and ice.
Actual result
Polar bears only spawn on ice.
Polar bears only spawn on ice; they cannot spawn on snow or grass. This is makes it extremely rare to see them in snowy tundra biomes.
Steps to reproduce
- Open the test world. It consists of a 4-chunk spawn platform in a void frozen ocean world. Command blocks in front of the player switch the platform between snow, ice, and grass. Repeating command blocks Mark polar bear spawns with purple concrete and kill everything to keep the mob caps open.
- Set the platform to snow.
- Wait a long time.
- Repeat steps 2-3 for ice and grass.
Expected result
Polar bears spawn on snow, ice, and grass, or at least in snow and ice.
Actual result
Polar bears only spawn on ice.
Polar bears only spawn on ice; they cannot spawn on snow or grass. This is makes it extremely rare to see them in snowy tundra biomes.
Steps to reproduce
- Open the test world, MCPE-105221 Polar Bear blocks.mcworld
- Set the platform to snow.
- Wait a long time.
- Repeat steps 2-3 for ice and grass.
Expected result
Polar bears spawn on snow, ice, and grass, or at least in snow and ice.
Actual result
Polar bears only spawn on ice.
relates to
Top slabs also allow spawns while being transparent/non-solid blocks. These are specially coded exceptions to the general rule that mobs only spawn on solid blocks. Moreover, polar bears are specifically coded to only spawn on ice in the frozen ocean biome so that mother bears and cubs will not get separated on the icebergs: see MCPE-105221. So I think this is working as intended.
Ice is also used in a lot of mob farms because of its unique properties of allowing spawns on top and spawn collisions on the side, and also heavily reducing light levels.
This issue was fixed in one of the 1.16.100 betas prior to this report being created but I did not know that at the time.
In 1.16.100 polar bears now spawn on ice, snow, and grass in snowy tundras, and on ice-only in frozen oceans. It is evident that a change was made in the polar_bear.json spawn rules file, because there are now separate sections for ocean and !ocean biome tags.
This is consistent with the intention stated in the Aquatic Update announcement that spawning on ice-only in frozen oceans was necessary prevent mothers and cubs from being separated.