Rico taking out the first tanker bug they encounter using his old future-football moves to get onto the bug, then blasting a hole in the bug's back and throwing a grenade inside. It's topped later by Dizzy killing one by tossing a grenade into its open mouth.
The Bugs turn the aforementioned Klendathu drop into a win for them, killing 100,000 troopers in the first hour of combat. By the end of the battle, the human body count has risen to over 300,000. In addition, if you listen, during the battle you can hear a com intercept stating that the Bugs are overrunning the retrieval ships.
During the film's second battle sequence, an unfortunate trooper finds out the hard way that Bugs too know how to Kill It with Fire.
Zander's defiant, prophetic Last Words: "One day, someone like me is gonna kill you and your whole fucking race!" He might have been a tool for most of the movie but he died like a man.
From the Marauder's opening battle, the troopers on Roku-San use reasonably legitimate infantry tactics for the first time in the entire film series, utilizing mutually supporting groups of soldiers, grenadiers laying down heavy supressive fire so the riflemen could advance ahead of them, etc. They only lose the battle because of The Mole sabotaging their defenses.