Is the average role-playing game not quite an accurate enough mathematical representation of the universe for you? When you’re playing science fiction do you prefer the science to the fiction? Especially the parts that involve math? If you answered “yes” Harp SF is just the right game for you.

The core rule book of Harp SF is very much a core rulebook, even starting with the obligatory explanation of what an RPG is and how to people play them. This is interesting because, as good as this game is for what it is, I would not recommend using it as an introductory system for a new player. The game comes in two volumes, Harp SF and Harp SF Extreme but can be played only with this core rulebook. The other book includes things like vehicles and animals and more detailed rules for both than what is included in this book.

While Harp SF can very easily be used as a genre specific but setting agnostic system, there is a setting included in the book so players and DM’s (called SysOps in this system) can jump right in without having to create an entire universe from the ground up. That universe is called “Tintamar” and is pretty interesting even without the system.

The first thing they provide for the Tintamar universe is the sci fi trope I like to call a “future history.” Like many science fiction universes, they provide a timeline starting from the recent past of the real world proceeding forward to the “current time” within the game. This includes all the major milestones including when the technology involved in faster than light travel was/will be invented, colonization of other planets, first contact with other species and interstellar wars. The nice thing about this timeline is that it not only addresses future history from the human point of view but also includes the timeline from the point of view of the alien species in the universe.

There is also a cosmography given for the Tintamar universe. Of course, this does not include everything but focuses on both human and alien dominated areas. There is a focus on the human dominated areas of the universe but the strongholds of other alien cultures are also noted. While the description of the universe is not exhaustive (how could it be?), it is exceptionally thorough. This section doesn’t include any game specific information and could serve as a good guide for any science fiction system.

All of this comes before the character creation section, breaking the usual mold for the layout of role playing games. There are benefits to this method, though. It allows players and GM’s to really immerse themselves in the universe before having to think about their characters. It is odd, though because it is a lot of information to get through before getting to the actual rules for playing the game, which is usually the hook to get players into the system.

In another tradition that breaks traditional format, when character creation finally comes around, it comes in a strange order. For instance the options for a character’s “profession” which is basically a character’s class, comes before descriptions of the species that are available to play. There are rules for playing characters with multiple professions as they progress and the system uses a fairly standard XP system. Over all, this portion has a feel much like a lot of other games, most notably several different editions of D&D. This is not a bad thing, as it will be familiar to a lot of players, especially the ones who might find this game particularly enjoyable, and, much as some people might like to, there is little need or room to reinvent the wheel when it comes to this sort of thing. Things feel more open ended than any edition of D&D, though and there is no limit to how many levels a character can have and a player could simply continue to add professions to their character as long as they liked to play them.

Just as odd when it comes to the order in which the information is presented, the different stats used in the game are explained now and the modifiers from the different species are given but the method for generating and assigning them doesn’t come until much later in the book.

The species themselves are done extremely well, though. Beyond the ubiquitous humans and not one but two distinctly different reptilian species, there are some nicely odd choices. The Krakur are an excellent example of one of these species, being squid like beings. They are largely aquatic and invertebrates so they’re not too radically different from what a human would find recognizable but they are far beyond the usual cat people that make up the races in many science fiction settings. There is a species that is plant based as well and written in a way that encourages the players to approach them as a truly alien species with a truly alien mindset.

Harp SF delves into other sci fi tropes like genetic alteration. This is another segment where they do a good job, and they are exceptionally thorough, even going so far as to discuss the usual alterations selected for the different species, but it continues the trend of things coming in an odd order.

Because it is not until after this section that the Skills section comes. These skills are pretty standard, though, in what is a trend for this game, very, very extensive. Whereas, even in more modern versions of Dungeons and Dragons, for example, skills are relatively generic, with broad expanses of skills being included under a single choice, pretty much every skill is separate in Harp SF. Not only is there not a single shooting skill, but there are about half a dozen skills needed to encompass all the ranged weapons available in the game. There are a variety of skills to deal with melee weapons as well and just as many or more to take into account all the different sciences possible in a sci fi setting.

Following after the skills is a section of Talents. These function much like Feats or Edges from other games, providing advantages to characters that can’t necessarily be defined or accounted for by abilities or skills.

No system or setting could be considered science fiction without technology. Just knowing what is available can often inform players about the setting as much as anything else. Harp SF does not skimp in this regard, either. One of the features of this game are tables and lists and there is a crazy big list of equipment available. This goes beyond the simple and obvious topics of weapons and defensive items and includes things like various types of sensors and assorted medical devices. It does not include vehicles, though, which are one of the focus subjects in the sister book, Harp SF Extreme.

But even this simple, massive list of equipment is not the extent of options available. To take into account the widely varying levels of technology that can be evident in any science fiction universe, there is a nice, detailed section on how to adjust the equipment provided for these different technology levels. This is done well and keeps the list from being even larger to account for each different technology level without being too mathematically complex.

Also, keeping the list from getting even larger, there are standardized rules for integrating multiple devices into a single device and rules for miniaturizing different devices.

The game play rules are just as deep and complex as the character creation and equipment lists. The basic mechanic is percentile based with higher scores being better. The rolls are open ended and any natural roll from 96 – 100 explodes, with the new results added to the first roll. This can go on indefinitely, assuming the roller continues to score 96 – 100’s. And in a game as interested in reproducing reality as this one, the opposite has to be true, too. Just as there has to be a chance for exceptional successes, there has to be the chance for exceptional failures. Particularly low natural rolls induce fumbles. There are several tables to take into account all the possible tasks that a character could fumble and the disastrous results that could result.

The open ended nature of the rolls is not the only way to exceed a hundred, which is good as many tasks require a result higher than could be achieved with a percentile roll. Skills and talents as well as equipment and its quality can all add to a roll. But even these are just a part of the modifiers that can be applied to a roll. In fact, so many modifiers can end up applying to a roll, especially an attack roll that they end up looking like algebra problems.

And speaking of algebra, it actually plays a role in the game. The following appears in the text of Harp SF – d = √(2Rh + h2) where d is…something…I dunno…math-y. But apparently, this is the actual method for determining how far it is from any point and the horizon on any planet. And this is not the only time when an actual physics equation is included in the book. The formula for calculating acceleration due to gravity is also provided, for example.

Despite this focus on actual science in this sci fi game, the potential for magic is mentioned throughout. Because this system is based on the basic Harp system, and the Harp system focuses on fantasy, it is repeatedly pointed out and the rules take into account that magic could occur in one of these science fiction settings, though it does not exist in the setting provided, Tintamar.

They do flirt with magic, though. The system gets as close to magic as it can without saying it with the psionics rules that are included. Actually, they go to fairly extensive lengths to point out the quantum mechanical explanation that could explain psionics, so that there can be no mistake that they aren’t magic and are science. This keeps the game in relatively hard science fiction territory despite the lack of hard science backing up the concept. And to make sure there’s no mistake about there being any hand waving “magic” these rules are just as complex as any other in the system. There are many modifiers and variables that go into each psionics attempt and each usage requires points from a character’s pool. But even determining how many points each power needs requires math as each power has several variables with their own points costs.

Though the system is realistic about just how terrible it is to get shot or otherwise injured in combat, it is hard to imagine an RPG that doesn’t include at least the potential for characters fighting and getting hurt. Damage in Harp SF includes criticals and these are an important part of combat, not something that happens on rare occasions as in other games but a regular part of a fight. And, true to the design of the game, these criticals are listed out in tables and there are a LOT of them. In fact there are 30 different critical tables that take into account pretty much any kind of damage a living being could take. I would be hard pressed to come up with a method of injuring someone not taken into account with one of these tables.

The players aren’t the only ones with math to do, though and the SysOp has some, to do as well. But, there is some subjectivity to what the SysOp gets to do. After all, experience points are integral to this type of game and there is a formula for this as well. It is not a straightforward formula and includes factors such as how dangerous the challenges the characters faced were, how far they advanced the plot by overcoming those challenged and how well they overcame those challenges.

There are a lot of things to like about Harp SF and I suspect that for the sort of people who like this genre, it might be perfect. After all, this game is meant to appeal to people who like hard sci fi and if you’re going to go in for hard sci fi, you want it to be as accurate as possible and don’t mind doing the math for it. This system does that perfectly.

Harp SF is full of lots of tables and formulas but it is exceptionally coherent. If you’re not opposed to keeping track of lots of modifiers for almost every roll and doing a fair amount of math then it is an excellent way to reproduce a hard sci fi setting.