Welcome to the Generic Universal RolePlaying System!
With GURPS, you can be anyone you want – an elf hero fighting for the forces of good, a shadowy femme fatale on a deep-cover mission, a futuristic swashbuckler carving up foes with a force sword in his hand and a beautiful woman by his side . . . or literally anything else! Thanks to its flexibility, quality writing, and ease of use, GURPS has been the premiere universal roleplaying game for over three decades!
A Generic Alternative [ edit ]
While all of the previous options have focused on smaller publishers with rules specifically created for space horror, there is another option, which is to go with a more generic RPG, from a more established publisher ... and it doesn't get any more generic than GURPS.
GURPS for Space Horror [ edit ]
Although GURPS is generic, it has supplements for both the horror and space genres. For horror there is the (appropriately-named) GURPS Horror supplement. Similarly, for space there is GURPS Space, as well as a number of related source books such as GURPS Spaceships or GURPS Ultra-Tech.
Flight 13 [ edit ]
But perhaps most notable is that GURPS even published a space horror adventure, Flight 13 ... although unfortunately it was published for GURPS 3rd edition, not 4th (its current edition).
However, 3rd Edition GURPS books are easy to acquire, and also it's fairly easy to convert 3rd edition material to the latest edition of GURPS. This means that even fans of GURPS latest edition can experience this adventure, if they're willing to do a slight bit of conversion work, or just overlook some inconsistencies (see this thread on the Steve Jackson Games forums for conversion suggestions).
The adventure only had three ratings on RPG Geek (6, 6, and 8), but it was more well-received on Amazon.com, where all three reviewers gave it five stars. Steve Jackson Games also published a free supplement for the adventure, available here.
Why Should You Use GURPS? [ edit ]
Obviously GURPS generic-ness is both it's biggest advantage and its curse. You won't find any sort of special mechanics built-in to the system to promote a horror feel, like for instance the stress dice in the Alien RPG. This means if you really want a game that feels as much as possible like you're living in a space horror movie, one of the other options is probably a better bet.
That being said, GURPS is an extremely popular and long-lived system. Even today its 3rd edition ranks in the top 250 on RPG geek, and its 4th edition ranks in the top 100. If you are looking for a system that will be excellent for all sorts of other campaigns ... and will still do a very decent job of space horror ... look no further than GURPS (and possibly its Flight 13 adventure).