Simply put.
Not only the commoners on the Spirit Hall Empire's side, but the commoners of the Heaven Dou Empire, the Star Luo Empire, and all across the continent could all be considered reserve soldiers of the Spirit Hall Empire.
This was a battle whose outcome had been decided before it had even begun. Since ancient times, whoever won the hearts of the people won the world.
The unification of the Spirit Hall Empire was now the shared hope of the entire continent! All commoners on the continent hoped that the Spirit Hall Empire would win, and were even willing to contribute in support of it.
Su Chen deserved credit for spreading these ideas, but the greatest credit actually belonged to Spirit Hall's efforts over all these years.
Spirit Hall had always helped commoners awaken their martial souls for free, and had led the two great empires in providing subsidies to soul masters. Its reputation had long been well established.
No matter how tyrannical Spirit Hall might have seemed in the eyes of the two great empires, in the eyes of the commoners, Spirit Hall treated them well and asked for nothing in return.
If that had not been the case, then no matter how beautifully Su Chen spoke, the people of the world were not fools. How could everyone possibly have believed him?
In other words.
If Su Chen had sided with the Heaven Dou Empire now, and the Heaven Dou Empire wanted to wage war against the Star Luo Empire, then no matter how eloquently Su Chen described a bright future, no one would have believed him.
In short, Spirit Hall could not be called exceptionally good, but it was absolutely not the villain either. Among the many powers of Douluo Continent, it was the best of them