Starfinder is a complete roleplaying game, and can be played on its own without ever referring to the Pathfinder Roleplaying Game. It is based on Pathfinder, of course, and shares many similarities with its older cousin, but in many cases Starfinder handles specific issues differently than Pathfinder. We've mentioned several times that Pathfinder is easily integrated into Starfinder, and that there's some level of compatibility between the two games, but we haven't been very specific on exactly how easy it'll be to add Starfinder cybernetics to Pathfinder fire giants, or port Pathfinder character classes and races into a Starfinder campaign. Those questions are likely to take more than one blog post to cover, but we wanted to at least begin going into greater detail about how we envision these two games working together.

Illustration by Hugh Pindur

Starfinder should feel very familiar to experienced Pathfinder players, and much of the overall play experience is similar. Despite changes like iterative attacks for high base attack bonuses being replaced by universal full attacks allowing two attacks both at -4, or breaking hit points into two pools of Stamina Points and Hit Points, most of the general rules of the game are close enough to make it easy to see how to convert a specific option from one class to another. The most common specific tweaks to combat are covered in the Starfinder Core Rulebook, specifically Chapter 13: Pathfinder Legacy. This chapter presents the information a GM needs to convert between the two games when dealing with questions of bonus types, actions in combat, CMB/CMD vs EAC/KAC, damage, ability scores, and so on. A GM wishing to take griefgalls from Bestiary 5 and use them for an invasion of Absalom Station should have no trouble adapting the monster to Starfinder use. In fact, given that both Starfinder and Pathfinder inhabit the same fictional universe, we specifically designed the game so that you could use monsters from one in the other on the fly, with little conversion—after all, a keketar protean is a keketar protean regardless of system, and this way we can focus on creating cool new creatures for Starfinder rather than just converting all the old standards.

For things like magic items, spells, feats, equipment, and other player-facing options, conversion can be more difficult and have more hidden pitfalls. One of the hardest questions a GM will need to answer is if something from one game system even should be introduced to the other. For instance, Starfinder and Pathfinder make different assumptions about when in a campaign various options first appear, and when they become commonplace. This means that introducing a new options from one of the games into a campaign using the other set of rules can have consequences well beyond how well the two sets of game rules interact mechanically.

For example, every first-level Starfinder character is likely to have armor that protects against extremes of temperature and pressure, and provides breathable air, thus protecting them from gaseous poisons or even complete vacuum for up to 24 hours. In Pathfinder, that level of protection isn't available until much higher level, and many characters never acquire it. While the rules for extreme environments are similar enough that a character from either game can make the appropriate saving throws (and understand how to apply the effects of failing those saves), a Pathfinder game that introduces items and abilities designed for Starfinder is going to bypass or neutralize a lot of common Pathfinder threats and encounters. Similar issues arise when discussing movement, flight, senses, ranged attacks, access to energy damage, and even the ease with which non-spellcasters can access magic abilities.

Those differences in assumptions alter how items and options from one game will impact campaigns using the other game's base rules. Even with the differences between Armor Class rules in the two games, it's not hard to figure out how a suit of ceremonial vesk overplate with a jet pack and infrared sensors would operate in Pathfinder—but the impact it would have on a typical Pathfinder game is much higher than the low level of those options in Starfinder would suggest.

Similarly, the two games also use different methods to produce the numerical values characters and monsters use to interact with one another. This often includes math that is (quite intentionally) behind the scenes, and thus not particularly obvious. For example, Starfinder does its best to not require characters to constantly get higher and higher enhancement bonuses to attack rolls, damage, and armor class, or resistance bonuses to saving throws. As a result, there's no option to create a +1 plasma cannon in Starfinder, since the additional math isn't needed. Thus adding magic to Starfinder gear is always about gaining some cool new option or ability rather than just numbers. It would be easy to determine how to port such rules over from Pathfinder, but doing so would create imbalances, since the new game is designed to function without most pure bonus-boosters.

For races, these issues are much less likely to cause significant issues. We already provide full Starfinder write-ups for dwarves, elves, gnomes, halflings, half-elves and half-orcs in the Pathfinder Legacy chapter of Starfinder. Those races still exist in the Pact Worlds, they just aren't as common as they were in Golarion-focused games using Pathfinder. Converting other Pathfinder races should be straightforward, and unlikely to cause major problems. In fact, some races that don't fit well in most Pathfinder games may be less disruptive to a Starfinder campaign!

Pathfinder classes are going to be the element it is most difficult to move to a Starfinder campaign, and require some work on the part of a GM, both in understanding how Starfinder handles various kinds of abilities and in looking for places where problems might crop up from unbalanced bonuses that Starfinder doesn't need or abilities that lack the support in one game system or the other. Of course, we tried to make sure common character tropes could be created in Starfinder, even if they're built differently than their Pathfinder equivalents. While there's no straight-up paladin analogue in Starfinder, a soldier with the priest theme, phrenic adept archetype, and various psychic power feats can certainly take the role of a religious champion with access to both martial skills and magic powers.

If nothing but the original Pathfinder classes will satisfy, however, the Pathfinder Legacy section gives what guidance we could manage for GMs wanting to port Pathfinder classes directly over. Questions of key ability scores, stamina points, skill points, weapon and armor proficiency and specialization, and other common core game mechanics are easy, and we mostly spell them out. When it comes to tougher questions like class features, eidolons, animal companions, familiars, class spell lists and 7th-9th level spells, bardic performance, and even flurry of blows we give advice, but it'll be up to each GM to decide exactly how to implement that advice.

In many ways, all of Pathfinder is like a series of "Starfinder Unchained" books—optional rules and subsystems a GM can adapt or not as appropriate for their game and their own desire to tinker. Our first priority was always to make Starfinder the best game it could be on its own, with as many robust options as we could make fit without overcomplicating it. Yet its underlying game engine remains close enough to Pathfinder that anyone who wants to adopt or convert materials from those sources to Starfinder should be able to do so with a minimum of effort.

Owen KC Stephens

Developer