Continuity mistake: Xiao Meng spent some time wrapping her father's (Professor Tao) left hand, going around his wrist/thumb and under his thumb (diagonally across his palm). When Tao was blown off the bridge and landed in the dirt, the bandage was NOT wrapped around his thumb (just around his wrist). (01:12:33 - 01:16:03)
Factual error: The scene where the Jeep gets stopped with its front tires on a lava flow wider than the hood and a lava flow under the cargo area is unrealistic. The lava or rising heat would be enough to damage belts/hoses. Zhang Nan would not be able to stand on the Jeep's hood that long (without injuries/burns) due to the intense heat. Crouching near lava is not as hot, so a person could withstand the heat for a few seconds under certain conditions, but not minutes like Zhang did standing on the hood. (01:09:53 - 01:10:25)
Revealing mistake: A lot of the CGI was quite good and, even if not totally realistic, was interesting and exciting to watch. However, the man supposedly rappelling (or abseiling) down the mountainside was obviously not there - his feet didn't touch the mountain. (00:36:10)
Other mistake: At times when everything was covered in ashes, Jeeps being driven over ashes had clean tires (black tread). One Jeep that was airborne for a couple seconds (coming out of a fire) had clean tires, but the tires later got dirty. (01:04:27 - 01:09:46)
