Come hell or high water
Scientists have officially confirmed the presence of liquid water on sister red, and while we've known about Mars' collection of ice for some time, the fact that water can exist in liquid form increases the planet's habitability ten-fold. That means the chances we (or something else) could actually live there just got way better. Just listen to Bill Nye explain it if you don't believe.
A building that looks exactly like Master Chief's helmet
You probably couldn't spot this from a satellite in orbit, but there's definitely a building on Mars that's built in the shape of Master Chief's helmet. We've seen it ourselves as we explored the wastes of the great cities of Mars and broke through the Cabal Iron Line in Destiny. It sits there as a monument to Bungie's most famous green-clad space marine - or it could just be a coincidence of level layout and art design. Whatever it's meant to be, it's much more exciting than a little bit of water, right?
Plans for a superweapon
We've got plenty of water on Earth as it is (California's severe drought notwithstanding), so the thought of quenching our thirst in the middle of a barren red desert isn't all that exciting. But if there's anything that instantly piques humankind's interest, it's weapons of mass destruction. According to Mass Effect 3, Mars is where those crafty, ancient aliens known as the Protheans stashed schematics for the Crucible: a galaxy-shaking, orb-shaped ordnance with the power to decimate the Reapers. Our species has yet to be threatened by any armies of colossal, bass-thumping space-lobsters, but we'd probably build the Crucible regardless to establish mutually assured destruction with any extraterrestrial lifeforms.
Volcanic flora and fauna that really hate giant moths and lizards
Godzilla: Monster of Monsters for the NES seems to take place in another reality. The giant monsters everywhere arent what make it unreal. They seem pretty normal, actually. Its that the very surface of every planet in our solar system seems fully capable of instantly destroying giant monsters. Consider the surface of Mars. Rather than the cold, dry wasteland of rocks and sand were familiar with, Godzilla and Mothra have to run a gauntlet of angry firebirds, lava and boulder-spewing volcanoes, and the occasional dragon that lives inside of those volcanoes. Everything on the surface of this planet wants Mothra and Godzilla to die, immediately. Hey, Mars, theyre from Earth! The lack of oxygen will kill them fast enough. Stop trying so hard.
A massive, corrupt sporting league pitting giant robots against each other
Of course everyone wants real-life giant robot fights to happen. No one thinks that watching a three-story-tall metal biped hitting another one with a scythe made of neon green lasers would be boring. The logistics are admittedly tough; where can giant robots fights and not mess everything up? Mars, apparently. The sinister corporations running Virtuaroid battles in the world of Segas Virtual On: Marz converted the entire red planet into Limited War arenas. What are Limited War arenas? Fancy spaces for giant robot fights. Brilliant, salmon-colored sunrises arent the only Martian beauties in this universe. There are also robots with metal pigtails that make other robots explode by shooting them with giant hearts made of plasma.
The shattered corpse of a Cyberdemon with a Doom-guy fist through its skull
When you're eternally damned to suffer in the pits of Hell, visiting the desolate, lifeless surface of Mars is practically a tropical vacation. That's likely what spurred waves of demons to make Mars and its moons their holiday getaway; nevermind all those unnatural portals opened by scientists-turned-crazy-cultists. But what those Imps, Hell Knights, and Arch-viles weren't counting on was a bloodthirsty space marine waiting for them on the other side, with a sawed-off shotgun in his hands and a zealous grin on his HUD-framed face. If Mars' atmosphere can't support flesh-eating bacteria, the bullet-riddled bodies of those poor demons could theoretically litter the planet for eons.
A rainbow-farting unicorn-turned-gun
Life on Mars is no picnic, according to the chronicles of the Red Faction series - disease and hardship brought on by rampant corporatism are a fact of life for the red planet's settlers, and when they finally carry out a successful revolution, all they get in return is the destruction of their terraformed life bubble and war with a vicious alien species. Something has to break up the onslaught of misery without getting in the way of their not-getting-killed efforts, and I guess that's where a rainbow farting unicorn gun makes logical sense. Adorably named Mr. Toots, he can fire a colorful projectile fart powerful enough to obliterate anyone or anything that gets in your way. Such joy and destruction in one little package.
A vinyl goddess(?)
Granted, we never actually see the Vinyl Goddess from Mars on Mars, since the entirety of her game takes place on an unknown planet where she crash lands on the way to an intergalactic B-move convention. That's not a joke, by the way, it's a statement of fact. Regardless, I'll give her the benefit of the doubt and assume that she actually is Martian, because that opens up a lot more interesting lines of inquiry. Is she from a race of Star Trek-ish bipedal extraterrestrials who look exactly like wildly attractive humans? Was she part of a Red Faction-style Martian colony, then broke out of abject servitude through low budget stardom? Are B-movies truly the one thing that connects us all across a thousand worlds? Man, where are the scientists when you really need them?
Tentacled martians, loyal to the Spanish
"Some call this place the new world. The Romans called it... Mars." So reads the opening to Jamestown, a Colonial Era shoot-'em-up where Christopher Columbus apparently got lost looking for Asia and ended up 140 million miles in space. The game opens in the year 1619 with the heroic Colonials battling the unholy alliance of Spanish and martian forces. Farming and industry have taken root on the Red Planet, and amid all the warfare humanity is thriving in their new home. Since it's been about 400 years since the events of Jamestown, Mars should be thoroughly colonized by now - and yet, all we've found is a little water. What happened to all the people? The aliens? It's like the lost colony of Roanoke all over again.
Giant silver spheres (which humanity immediately demolished)
If you picked up Rare Replay recently, then you probably got to relive the cross-country demolition rampage of N64 classic Blast Corps, in which you obliterate entire cities to clear a path for a runaway truck carrying nuclear missiles (typically to the tune of some sweet banjo-infused techno). But once you've wrought billions of dollars in property damage, the urge to destroy and all large objects becomes an addiction. That's why, when you make contact with some balloon-like silver spheres hovering just above the surface of Mars, your first instinct is to turn their destruction into a minigame, in which you crash into them in mid-air with a bulldozer after scoring sufficient air off of conveniently ramp-shaped divots in the red planet's surface. You have eight minutes to wantonly obliterate what could very well be alien life, but pro 'dozer drivers only need 16 seconds.
Biker Mice
C'mon, NASA. Just admit it. Not only did you find H2O up there - you also stumbled upon three hardcore, beefed-up rodent roadhogs and their underground racing circuit, presented in the same isometric manner as Rock n' Roll Racing. And you're just saving the photographic evidence of these Biker Mice From Mars until the buzz dies down on the whole water thing, right? No, no, it's fine. We'll wait.
