What We Know About Mars

Mars has become an increasingly important
theatre is the expanding conflict between the
Trilobyte Kingdom and Humankind
(above- a martian in Surfer Armor views a cresting Kilbit Worm

Martians alluded detection by Earthlings
for decades due to being (like all other planet inhabitants
in the solar system) subterranean dwellers.
Over the past 30 years or so the two cultures
have established diplomatic relations,
with surprisingly little blood shed.
Language barriers were
quickly solved through technology. 
Though humans are still forbidden from
entering the inner Cities of Mars,
Martians have established joint bases
aboveground to work alongside the visitors. 
Martians wear "surfer armor" to protect
themselves from the elements and
because the Martian surface still has
pockets of unbreathable air
(despite decades of terra-forming).
There are two known types of martians,
known colloquially as "greens" and "clears".
Greens are opaque in skin tone
and regarded as a higher caste.
Clears, as the name implies,
have semi translucent green skin,
and are regarded as second class proletariat. 
As a fresh-faced, 18 year-old enrollee
in US Space Force, Rex Ganon
found himself 140 million miles from home.
He was tricked by a martian women
into removing his helmet for a kiss
and sustained heavy damage to his lungs.
It was only through an experimental emergency
surgery that his life was saved,
though he bares a mechanical torso for his folly. 
It has long been theorized that there is a direct,
sustained, vector portal somewhere on Mars
connecting to the Trilobyte Kingdom.
This hypothesis explains how Marson
was able to inure himself to the Trilobyte King,
without being a native of that dimension. 
A special garrison of Hyper Knights,
called Kaldors, patrol Mars for the King.
They are solitary types and prefer to
sleep outside rather than
interact at any of the aboveground bases.