Act 1: Gold Mining - You're a miner. You mine gold in this quasi-training level (and blast animals for fun if you like).

Act 2: Discovery - Underground bunker, wha? It's a small installation with some kind of passive defenses built in. Maybe an automated turret, etc? It's clearly native, not built by your fellow colonists. You discover somehting somehting important, maybe coordinates on the planet for the next act?

Act 3: Following the info found in the previous place, find another, much larger bunker installation, and the objective is to raid it and see if there's anything valuable inside?

Act 4: You bump into one of your rival colonists! He's generally an ♥♥♥hole and gets in your way. Objective is purely about collecting more gold so you can buy equipment to go explore more sites on the planet.. maybe collect a set number of components, the first of which was discovered in the previous mission? But the other guy is on the map too, and he's causing trouble... maybe he's also found a piece of the artifact?

Act 5: Rivalry continues... maybe this time you're both trying to search an installation? Rush to get the artifact piece! Argh.. coding the AI for that may be tricky though. But probably doable, however, with some fudges. Still need to collect gold to finance the continued struggle!

Act 6: In your eagerness to raid the last place, you set something off, and now there's suddenly swarms of robots attacking you! Defend yourself or die! This is on the surface of the planet, and you're defending your bunker... perhaps the same one from the last scene?

Act 7: Defend the Station - Space Station Alpha (or whatever) is under attack! Defend it! Whatever you awakened is very pissed off! It's attacking the station, storming it with its remote-controlled robotic bodies, etc... We have to figure out how to represent the space station/city; thoughts about animating the gravity vector and causing mayhem (either the station is tumbling in orbit, or the artificial gravty generator is going haywire). Maybe it's all in 0-gravity, and you're this little floating pod with a gun attached to it, and tiny jets to navigate the station's interior? This is a very different experience from the rest of the game, almost like a bonus stage? Maybe in the battle, many colonists' (brains) die, including your rival?

Act 8: Moon Mission 1 The attacking robots came from the moon! Maybe that's where the resident intelligence is? Basically, go there and explore... Environment is low-grav, presents different challenges. There's still gold to be collected.

Act 9: Moon Mission 2 You are attacked again, but now on the moon's surface, and by really big and tough baddies! They seem to be generated from these auto-factories which just churn them out. You need to fight your way to and destroy these spawn points. Upon completion, you discover the command and control location of the Resident!

Act 10: Final Boss Fight - HUGE installation, with a HUGE brain at its core! Super tough fight, super tough enemies, coming from spawn points all over! Your weapons will be overheating (not really, no plans for modeling weapon heat) by the non-stop use. You will lose many many bodies trying to penetrate this place and defeat the Resident! Tons of traps, mines, turrets and spawn factories here. It should be really really satisfying to beat this level. I'm talking NES-era difficulty.

Yup. It's because the engine can't handle real borders(or something) yet. Data could explain it better but he's like a ghost.