The initial concept was very simple. In the middle of the board is a planet. Astroids fly in and you have to touch the astroids to protect the planet. The initial name was "World Defence".

Our first test of gravity and the planet. This was built in a couple days. Semi-realistic sprites were used. As you can see, the astroids are falling in towards the planet... and they don't explode. So, if you kept the game going, you'd just have a huge set of astroids surrounding the planet.

Another detail of this is that Josh used formulas developed by Einstein to simulate the gravity of earth. We could see the astroids already "slingshoting" around the earth and thought it was really cool. That was something we weren't expecting, but thanks to good physics, makes the game a bit more fun.

This was actually a mockup. Though, its just some photoshopping on top of the real gameplay. We were trying to figure out how to show that the earth was getting hurt. Aka, if you failed too much and too many asteroids hit, then the earth would need to get damaged.

The other part of this mockup was the satellites. The concept was that when you touched an asteroid, satellites would fire a laser that would blow them up. That way, the game has internal consistency on *how* the astroids are blowing up.

And finally, we were experimenting with *huge* astroid trails to make them seem more violent and serious. So, that's the big fire trail you see on there.

We felt that a "health chart" was too contrived for the game. Why have to have a chart? If the earth was getting damaged, then you'd be able to see it, right? This is my attempt at modifying the original image into a large set of "hurt earth" graphics. So, as the earth got hit more and more, eventually it would be nearly splitting in half (as you can see in the last image). That way, when you lose and it "explodes", you aren't caught offguard.

Interface without having to be all nerdy about it.

Josh, the Lead Developer, wasn't a fan of the photo-realistic angle and wanted to give something more organic a try. He worked with an artist and the results look really good... but the problem was that they just don't match with a space game! It doesn't look like a space game anymore. It looks like a city-builder or something more friendly.

We needed a new approach.

With the initial concept work we had discussed doing it as an oldschool arcade game. Josh and I both agreed that would be a good direction to go in. So, we started working on that.

You can see here a partially-damaged earth (its fragmenting), with the 5 satellites, and full shields (a concept that initially started as "moons" actually).

Its kind of neon/futuristic.

But... its really busy. So many layers! It was time for the satillites to go bye-bye. Since this game wasn't realistic anyway and the lasers were so hard to deal with... we didn't really need the defence system anymore. In an arcade game, its more OK that touching just destroys. The story of the game is no longer one of simulation, but of simple, classic gameplay.

This is the start of the game in the near-final version. No shields are up (you get them through powerups) and there are two astroids on the way to kick some planetary ass.