Infantry Troopers: Even though they are hopelessly outclassed when fighting one on one against an alien human infantry troopers still contribute to the battle by overwhelming their enemies with sheer numbers.
And there are exceptionally individuals among them who can turn the tide of battle even in a fight between titans. Like Sgt. Brawler who once defeated an alien warrior with just a knife. Or Captain Sophia Stella who once defended an outpost along the side of a lonely infantry whale for 48 hours straight before help arrived.
Human Troopers
Human Suit Mark I: The first human suit was created as an answer to the alien battlesuits. However mankind had just returned to creating tools of war and still had to recover a lot of knowledge. Therefore the mark I suit turned out rather clumsy and ineffective. It was soon replaced by the mark II suit. Today it is still used for guard duties or in very desperate situations when no other equipment is available.
Human Exosuit Mark I
Human Suit Mark II Much more agile and better armed then its predecessor the mark II suit has become standard human assault vehicle. While it is more mobile and better armed then the mark I it is still no match for either the aliens or the whale suits. Humans can only control their suits via conventional steering unlike their whale allies who use telepathic commands to make their suits move. And humans lack the multitasking power of the alien’s double brains. Therefore their reaction time is much slower. However it enables the humans to provide important supporting roles for their whale brothers.
Human Exosuit Mark II
CyborgTroopers: In the early days of the invasion when humans still thought they could defeat the invaders without the whales a special science project was created to give the humans an advantage against the aliens.
The scientists tried to fuse small exoskeletons directly to the nervous system of human soldiers turning them permanently into cyborg warriors. These warriors proved to be effective against the aliens but the loss of humanity drove many of them insane after a while. The program was soon stopped and the whales stepped in to fight along the humans. Some cyber troopers still fight in the armies of the Whale-Human Alliance today.