I tinkered with Clickteam Fusion lately. Despite its age I still find it quite capable of quick and easy game development, provided you keep the scope small. I like the built-in texture packer that automatically creates a sprite sheet from all your images when exporting to HTML5. Also I do like that you can play back MOD music files which are known for their small file sizes. You can find an abundance of these files here, and they are all public domain. However, a downside is that they are converted to OGG and MP3 when you build and run your game for HTML5. So, unfortunately, the benefit of a tiny file size is not given anymore. But apart from that, the actual runtime file is amazingly small, just 395 KB. The background music for my game can be found here. Toggle it on/off by pressing M during game play. Pause the game by pressing P. One more thing: I found a Procedural Sprite Generator quite useful in creating the enemy sprites for my game.

Retro fans can tell quite a similarity to NAMCO's Galaxian from 1979, but it's not an exact replica at all. I was always annoyed with the enemies' erractic sine-wave movements and never good at dodging. So I made the enemies more predictable when they rush at you like kamikaze pilots.

In this game, your mission is to take out waves of alien invaders. Each wave has 46 aliens, and there are four different types. Every level is about clearing one of these waves. Once you finish that, a new wave pops up, and a new level begins. There's no final goal to reach; your aim is just to survive for as long as you can, clear as many waves as possible, and rack up as many points as you can.

Meanwhile, the aliens are doing everything they can to take you out, too. Every now and then, one or more of them break away from the convoy to dive-bomb you, shooting at you and sometimes trying to crash into you. If they slip off the bottom of the screen before you manage to take them down, they'll just come back to the convoy.

The frequency of their attacks and the number of attackers both rise in the later waves. During the first wave, you might see two or three enemies attacking occasionally, and at times, the formation just hangs there and allows itself to be shot at. However, by the time you get to the tenth wave, you will be under constant attack.

A bonus life is added every 5000 points, but ONLY if you have less than 3 lives left.

You can only have one shot on the screen at a time, so you need to be careful and make each shot matter. When you're up close, you can fire shots in quick succession if they land, but if you miss, you probably won't have time to shoot again and will need to dodge the alien that's coming at you.

You lose a life whenever you are hit by an alien's shot or rammed by their craft, and when you lose your last life, it's all over.

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