You are a lone researcher on an outpost planet. You are contacted by mission control to tell you that a rogue planet has entered your solar system and will collide with your planet. That’s the bad news, the worse news is that they can’t get a rescue ship to you in time.  Oh and it is going to continue to take out the moon orbiting the planet and several other planets in the system.

Your only hope of survival is to find a way of hopping from one celestial body to another staying one step ahead of Planet X.

Inspired by a short story by Italo Calvino, “The Distance of the Moon”  http://www.aleastory.co.uk/The-Distance-of-the-Moon.pdf

“This is how we did the job: in the boat we had a ladder: one of us held it, another climbed to the top, and a third, at the oars, rowed until we were right under the Moon; that’s why there had to be so many of us… from the top of the ladder, standing erect on the last rung, you could just touch the Moon if you held your arms up…. I would cling first with one hand, then with both, and immediately I would feel ladder and boat drifting away from below me, and the motion of the Moon would tear me from the Earth’s attraction. Yes, the Moon was so strong that she pulled you up; you realized this the moment you passed from one to the other: you had to swing up abruptly, with a kind of somersault, grabbing the scales, throwing your legs over your head, until your feet were on the Moon’s surface.”

The solar system that you are in is very compressed and and each planet has multiple moons with wildly elliptical orbits, which at times take them so close to their planets and each other that they are almost touching.  

So the game play is to build structures to be able to transfer from one body to another when they cross each other’s path.  Each Planet/Moon being a level with it own unique problems (i.e. different gravity, raw materials, distances to transverse, lack of oxygen, etc.)

Fighting game where all contestants have a wolverine-like ability to heal. You would have to create a fighting system where the player models could be cut(deformed) and sliced(cut in pieces).  If a player's arm or leg is sliced or blown off, it starts growing back. You would need a system that adjusts the fighting moves dynamically based on the body condition, and a system to manage the body model. 

You could probably build the body in segments and create versions of each segment that animate the segment's growth.  The body would use a dynamic IK system to string together the pieces to form the whole.

You have to take the head to win, the theory being that if you sever the connection between the head and the heart, you break the ability to regenerate... that is why severed limbs don't grow into a copy of the original.

The scientists of Earth have been tracking Near Earth Objects (NEOs) and discovered two, larger than the ones that killed the dinosaurs, that will cross Earth's path.  Initially there was no concern because they were not on a collision course with Earth, but it has been discovered that they will collide with each other.  The specific outcome of this collision is unknown, but it will likely create a cloud of thousands of smaller asteroids with trajectories on a collision course with Earth.

Asteroid Command has been set up through an international consortium in a race to save the human race...

They will not be able to destroy them all, people will die, cities will be wiped out... Can man escape the fate of the dinosaurs?

gameplay
A real-time strategy and arcade game paying homage to the classic coin op Missile Command, the player needs to identify and destroy or deflect any object large enough to create mass destruction.  They will have a series of tools at their disposal, some of which (in development) will not come online until well into the game...
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Written intro... Then the game begins with the two asteroids impacting (the outcome different every time you play the game).

The first phase is analysis.  The computers identify all the pieces on a crash course for earth or the moon.  The list is filtered for only those large enough to take out small cities.

The second phase is planning, which resources to allot to which types of response.  Also, resources must be allocated for civil defense (evacuation, sheltering in place, providing emergency infrastructure).  This is a cost-effective mitigation measure for saving lives from the smallest NEO impact events and is a necessary part of mitigation for larger events. This phase plays like a resource management sim.

The third phase is action, target and launch missiles with the goal of destroying or altering the course of the asteroid.  This phase plays like a space flight sim.

The final phase is final contact.  Part of the defense is to launch laser satellites at key points in geosynchronous orbit over major continents to take out any remaining threats. This would be played arcade style shooting asteroids on their approach, as satellites become available with the rotation of the earth. Any missed asteroids would spawn animation of destruction and estimated body counts.

Playtime would be roughly an hour. 5 mins for analysis, 10 mins for planning, 30 mins for action, and 15 mins for final contact.