Asian language historical war drama about the Captain of the Guard of a city under siege by the emporer's massive army

The movie is set centuries ago. I don't recall any cannons (ie gunpowder) so it could be many, many centuries ago in China. There's a long portion near the end of the movie where the army surrounding them is building a massive earthen ramp that will allow them to ride right up and over the city's fortifications. Both sides know approximately how long it will take them to complete the ramp, and it creates this tense waiting period where the city inhabitants are basically counting down the days until the inevitable final massive battle.

It is a foreign language film that I saw subtitled in English. I don't know if it was made in China or Hong Kong or Korea or Japan, but pretty sure it was one of those. As for when the movie was made: I saw it about 3 or 4 years ago and I doubt it was more than 20 years old from the look of it. My guess would be mid-2010s maybe? What the heck is this movie?!