Minecraft wiki entry for Development_versions, associated text: Increased the chances of Axolotl naturally spawning in Lush Caves.
Fish now attempt to avoid Axolotls.
Magma Cubes are now correctly aggressive towards Iron Golems and Slimes are no longer aggressive towards Snow Golems (MCPE-51162).
Phantoms should now be able to free themselves after getting stuck when trying to pathfind into mountains (MCPE-119773).