The Grimly Brothers weren't as stupid or as ignorant about mechs as the native aliens.
Before they stabbed the Hullsi Wardogs in the back and exposed their true allegiance, the troops of the Grimly Brothers kept up with the news and acted like any other mercenaries.
They followed the latest developments in the mech industry as avidly as other mech pilots. They knew about the Ultimatums and listened to many of the wild claims about its performance.
Yet now that they had begun to fight against these mechs themselves, the troops of the Grimly Brothers learned that these mechs fully deserved all of the hype!
The hyper spaceburst shells launched by the modern heavy artillery mechs were not only relatively fast, but also exploded across a wider volume of space than the explosive shells of the previous generation.
The E energy empowering the explosive ordnance of the Ultimatums significantly increased the lethality of every explosion!