I pushed the Roman theme of my panther army a bit further

When surrounded by numerically superior light infantry, as is often the case when fighting yellowblins on the fringes of the empire, the legion can form the Testudo. Their shields can stop most light firearm bullets, forcing the enemy into either very long-winded attrition, or extremely costly charges. Then, ideally the horde loses steam pretty quickly and leaves the battlefield with heavy casualties. But when outnumbering their enemy at least 200 to one, they might want to keep pushing, suffering volley after volley of devastating machinegun fire until enough of them reach the static formation, and try their best to overrun it.
Alternatively, if the horde tries to rush the formation, it could mean that they're running low on ammunition, which would be the best case scenario.
And even if that happens, they can rapidly reform a defensive line behind the breach.

https://youtu.be/f3opK6whCH0