Planet's Edge is a 1991 DOS game from New World Computing primarily notable for being FUCKING HUGE. Seriously, if you cruise the abandonware* sites looking for some fun old game to play for a few hours, this isn't it. It takes a serious time commitment to play this game through, even if you breeze through the dialogue and hack and slash your way across space.

Ok, so we're all sittin' around one day, when when this freaky alien probe arrives at the Earth, and before you know it *POOF* it's gone. Not the probe, the Earth. The moon is still held in place by the Earth's gravity, but the planet is, to all other intents and purposes, gone. Spooky, no?

By an amazing stroke of luck, this all happened when the space ship Unity was about to go to Mars. The ship and crew are safe on the moon, and with the FTL drive salvaged from the alien thing, you set out to discover what has become of the planet - and possibly if it can be retrieved from the "space-time warp" it is apparently trapped in.

The Centauri Device, as the alien thing is called, requires eight Important Alien Doodads to repair, coincidentally scattered evenly throughout the eight sectors of known space. By an even more amazing coincidence, all eight sectors are arranged in a radial pattern - like a roughly-sliced pie, with Sol smack dab in the middle. You see where this is going.

While you don't have to do the sectors in any particular order, but they should be done in order of difficulty**, unless you enjoy frustration. The eight sectors in order, with their associated space doohickies included for no good reason, goes like this:

Algieba      Algieban Crystals
Kornephoros  Mass Converter
Caroli       Gravitic Compressor
Alhena       Krupp Shields
Zaurak       K-Beam
Anqak        Harmonic Resonator
Izar         N.I.C.T.U.
Alnasl       Algocam

Each sector contains between seven and twelve stars, each with one to ten or so*** planets. Some planets contain elements needed for the construction of ships, ship components or personnel equipment. Some are protected by space stations which must either be destroyed or bribed. Within each sector, there are between three and five planets which you can beam down to. Each planet is designed to be like a Star Trek episode, where your four characters beam down, maybe solve a problem, maybe grab some loot, maybe kill a whole lot of nasty alien creatures, et cetera.

There are six sets of ship plans and four sets of technical plans to be found as well, typically at the end of a sector-scenario. These allow you to build better ships and ship components, respectively. Also, various found items can be built at the moonbase. In fact, I recall having to go back to the moonbase at one point to ensure that all four characters had a stick. A special stick. Not that I'm bitter, or anything.

Space combat is apparently based on Star Fleet Battles, though I've never played that so I can't comment on it. Nasty ships wander around demanding cargo from you, and they can be a real bitch if you accidentally wander into the wrong sector.

Anyway, it's a must-play for any CRPG fan. It was written partly by Neal Hallford, who also wrote Betrayal at Krondor, and he tells amusing stories about it at his website Lots of the other people responsible worked on the Might and Magic series as well, so if you dig those, you may enjoy Planet's Edge as well.

*Home of the Underdogs is one place to find it. I didn't have much luck finding another source. Also important is the necessity of some kind of CPU slowdown utility. Really, you will not be able to play this even with some conventional slowdown technique. Your super-duper-CPU's internal cache will make the space flight unfeasable. I use DOSBox, and you should too.
**Difficulty here is only in terms of bad-guy-toughness, not some abstract index of puzzle difficulty or something.
***My memory is foggy on this point. It might be twelve. Meh.