Factual error: Not only Mulan's horse is able to outrun an avalanche (at the beginning even unseen by the large enemy army who does not even notice the event occurring), but it also gallops through it undisturbed while Honghui is being carried away depicted as being in serious danger. (01:09:30)
Suggested correction: This is consistent with what you see throughout the whole film: Mulan consistently breaks the laws of physics because her "Chi" is strong. (Translating it to the Star Wars lingo: Strong with her The Force is.) Five minutes before (video time, not in-film time) she reversed the flight direction of a spear. This is a fantasy film and is supposed to do all of this; we watch it knowing that magic, "Chi", and The Force are not real.
That's a composition fallacy.