I have not watched this yet. Is it Muay Boran? I know that, from a strictly historical perspective, the style used should be Muay Boran. Ayutthaya has not existed for centuries, and Muay Thai would therefore be an anachronism in any film set during that period. But most modern Thai martial arts stars are Muay Thai practitioners, and since when were action films concerned about historical authenticity?

I haven't watched the whole thing, but I bounced around between fights scenes. It's absolutely Muay Boran from the stance to the moves, etc. My gripe isn't necessarily with the film itself as it's an action movie, low bar, yadda yadda, but I saw an opportunity to neckbeard the description and I took it.