Updated steps to reproduce in comment.
The Better Together Update / 1.2.0.2 patch notes say:
"- Mobs will now avoid cacti, fire, and lava"
But they don't seem to avoid fire at all.
Avoiding lava seems to work perfectly for most mobs, except slimes. Slimes literally jump in lava.
How to reproduce:
Put a very simple fire maze/wall around a villager or a zombie for example
Most of the time they will just walk through the fire
Linked issues
Comments


FWIW, in 1.5.2 I see slimes jump right into very large bodies of lava all the time. It's not like there's a lava square and the slimes are so big they can't avoid it. They just hop right into a lava lake flowing lava pool (not lava source blocks) lava lake* and go poof.
*Upon further inspection, it was all lava source blocks. The correction has been corrected.
Cleaning up old tickets: This ticket has not been updated recently (~1 year+) so is being closed as Cannot Reproduce. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines.
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This bug is still in the game.
Please reopen this issue

Can reproduce.
Have a villager or zombie near lava with nowhere else to go. Instead of staying still, like they would do with any other threat, they jump straight into lava. IF it does not happen, repeat a few more times, or wait 10 minutes.

still an issue in 20w15a

@Balaram Chakrabarty This bug report is for the Bedrock edition, which doesn't have a version 20w15a.
You should make a seperate bug report for the Java edition.

Confirmed in 1.16.0.55 Beta
Reopen this report

Confirmed in 1.16.220 for villagers. Some mobs, for example sheep, do not avoid damaging blocks by design. These seem to be the creatures that are supposed to be less intelligent. So I think it is probably intended for slimes and zombies to not avoid fire and lava. We would also expect iron_golems to be undeterred by fire/lava because they are tough and have a more important job to do in defending villages.
Villagers, however, avoid rain, and I would expected them to be intelligent enough to avoid fire and lava. This bug may affect more than just villagers, and it may impact some pathfinding behaviors more than others (for example, moving to attack vs. random wandering), but it is easiest to reproduce by getting villagers to try to go to POI.
Steps to reproduce:
/gamerule dofiretick false
On a flat, solid surface, fill a 5 x 5 area with fire.
Remove the fire from the center block.
Spawn a villager in the center block (so that it is surrounded by 2 blocks of fire on every side.
Place a bed and workstation a few blocks outside of the fire.
Expected result
The villager does not move.
Actual result
The villager walks and jumps through the fire to get to its workstation.

Villagers pathing through fire to reach their workstations can be fixed by adding "avoid_damage_blocks": true
to their minecraft:naviation.walk
component.

Affects 1.17.40.20

I can still reproduce this issue (only for fire) in 1.17.40.21 Beta quite easily by spawning a zombie and a villager on opposite sides of a fire block in between, with space around the fire. The zombie still goes straight through the fire instead of pathing around it.

kmb: not all mobs are supposed to avoid damaging blocks. Zombies and sheep, for example, are notoriously heedless in real life.
If you still think there is a residual bug here, please make a new ticket so that we can track something precise. Note that a couple of related issues are already reported: MCPE-142054, MCPE-138191.

Mobs seem to be cutting corners when pathfinding, so they are still getting caught on fire (1.17.40.23, no experimental modes)

silentwisperer: Let's get a new ticket for that issue, as it would be broader than this one.
Also happens in iOS 1.5.0. Not only do the villagers walk through the fire, once they start burning they seem attracted to the fire and just circle around in it until they croak.