Minecraft wiki entry for Hoglin, associated text: If a hoglin spawns in or moves to the Overworld or the End, it shakes and then transforms into a zoglin after 15 seconds. Any lead attached to the hoglin breaks when it converts, even though zoglins are leashable. It is not known whether this is intentional or not, but it is more than likely a bug. ‌[Java Edition only][3] The newly-created zoglin gets Nausea I for 10 seconds. This Nausea effect is only decorative and has no effect on the zoglin's behavior.