I love the SF2e GM Core. It includes pretty much everything I could want in a GM guide, save just a couple nitpicky things. A lot of the community felt that the Starfinder Second Edition release was a letdown because the core books were staggered on release. I didn't feel that way, but I can understand why people felt that way.
Now that I've had some time to read through and use the Starfinder Second Edition GM Core at my table, I can say that I am even more invested in Starfinder Second Edition than I previously was. I truly hope that any feeling the broader community has about SF2e being incomplete is assuaged. The game now feels “complete” to me, even without the Alien Core being released yet. (There are a ton of creatures freely available from adventures and scenarios at this point, and if you have the PF2e NPC Core, they don't need much adaptation in many cases.)
Because I spend over 90% of my time with TTRPGs behind the screen, I was waiting for the GM Core with bated breath. So was it worth it?
Disclaimer: Paizo provided me a complimentary copy of the SF2e GM Core for this review. That has not influenced the outcome of this review.
I'm a Forever GM, and I Approve This Message
I have mixed feelings about GM guides. Some are good, some are okay, and some are…less than good. I'm not a big fan of the fifth edition Dungeon Masters Guide, either the original one or the 2024 remake. They're too focused on new DMs without enough content for veterans to take and run with (though the 2024 version does have more of that with the Greyhawk stuff and Bastions). Kobold Press's Gamemaster's Guide for Tales of the Valiant, on the other hand, was filled with alternate systems and rules that I could incorporate into games without feeling like I was an afterthought.
I hoped that the Pathfinder Second Edition GM Core was a roadmap for the SF2e one, and I was right. In many places, the content is similar, if not exactly the same. The rules for building and running encounters and creatures are very similar, and the numbers line up 1:1 from my comparisons:
The differences are what you'd expect. Hazards like laser webs and zero gravity and solar flares aren't something most Pathfinder games have to deal with, but are incredibly common in sci-fi settings. So it's definitely not a copy/paste situation, and there's a lot of stat blocks and rules I'll be referencing a great deal as the sessions go by.
The lore in the book is a great supplement to the Galaxy Guide, and the different kinds of hazards and obstacles, environment rules, and afflictions are organized well and aren't just repeats of Pathfinder ones. After all, you can't get the “social media addiction” affliction in the past, nor can you get caught in “microtransaction hell.” I have read rules on airlocks and catwalks and radiation sickness. These are all things I've needed during the playtest but didn't have.
If you already have the Pathfinder GM Core, you have the most basic parts of this book already. You can create creatures and such, and run the numbers already. However, there's so much more to this book than just that. It's worth picking up on its own merits, for sure, 100%.
The Big Selling Points
I do a lot of homebrew and content creation, so having the charts and numbers to create things is always going to be the biggest selling point for me. So once I verified those were there, as were the standard treasure levels and stuff I've come to depend on throughout the playtest from the PF GM Core, I needed to know about computers and hacking rules, starships and space combat, and anachronisms.
Starships and Space Combat
The biggest exclusion from the Starfinder Second Edition Player Core was certainly space combat. While tactical ship combat is due to come out in next year's Tech Core, along with the technomancer and mechanic classes, the GM Core has an updated-for-2e version of cinematic starship combat first seen in the first edition Starfinder Enhanced sourcebook.
In this version of ship-to-ship pew pew pew, the GM will run them like complex hazards, a system that already exists in the game. Players have specific actions they can take based on the different roles they fulfill on the ship, such as captain or science officer, or gunner. You go through initiative, and resolve the encounter based on the victory conditions.
The system is…fine. It works as it's presented, and if you have a really flavorful GM, I think it can be a lot of fun to give your crew some truly operatic moments. But it's very dependent on how well your GM and group handle hazards and obstacles, whether it works well for everyone.
I look forward to seeing what the tactical combat looks like when Tech Core comes out. That said…there are no spaceships in this book. While there is a “Vehicles” section with some pretty neat stuff, and my party has already bought a helicopter…err…an enercopter.
They did the beginning part of an adventure path earlier this year, where they were given a starship, but what I wanted out of the GM Core was pricing for ship upgrades, even buying a new ship wholesale. Instead, the GM Core says “starships, buildings, businesses, and other such assets don't cost the PCs credits to purchase and can't be sold for credits—they're a narrative device meant to help you tell a story.”
The best I've got right now is that a space-faring jetski called a wakeskimmer costs 28,000 credits, and a drop pod costs 2,500 credits. I can extrapolate it out, but my PCs have straight-up asked me how much they'd need to buy a new ship. While I am all for handwavium in TTRPGs for many things, specifically excluding spaceship pricing in a space game—especially one that's as reliant on rules and numbers as a -finder game is—is a glaring oversight.
Again, I am really looking forward to the Tech Core to hope we can at least get some examples.
Anachronistic Adventures
In the Starfinder Core Rulebook for first edition, there are stats and lore entries for the “standard” fantasy races like elves, dwarves, and so on because Starfinder is a science-fantasy game. Those aren't included in the 2e Player Core or GM Core, however, because you can straight-up use the ones from the Pathfinder Player Core.
What is included, though, are sections on running what they call “anachronistic adventures.” These are broken up into 4 subsections:
- Timeshifted Adventures, where either a PF character finds themselves in the SF world. (I currently have a Wizard in my party like this, and it's great.)
- Archaic Adventures, where SF elements are used in a Pathfinder campaign.
- Anachronistic Creatures, which deals with using one game's monsters in the other. How does a plain ol' dragon compete with its teched-up kin, anyway?
- Anachronistic Gear, in which you get guidelines on the major differences in gear between the two games.
But are these sections useful? Yes. And for one big reason: they explain that even though Pathfinder and Starfinder use the same engine, they aren't 100% backward compatible.
For instance, crafting takes much less time in Starfinder. Why? Fabrication technology exists. Medicine is better, not even considering healing magic in the world. Buying items is different because of fast delivery via drones or searching via the Infosphere to find just the right thing.
Armor is better in the future, laser rifles are straight-up better than bows and arrows, etc. These chapters go through the classes and various things that you can bring back and forth between games, and then tell you how to adapt them without breaking things.
And, if you're like me and running a PF game a couple of days after a Starfinder one each week, it has been a help in figuring out balance with how easy it is to get darkvision and flight in SF versus in Pathfinder. Things like that change the game dramatically, and these sections break them all down one by one.
Dynamic Hacking
Like the starship combat, the dynamic hacking is based on complex hazards. I like that these exist with some examples because just a few weeks ago, I was having a hard time coming up with some mid-battle hacking consequences and could have used something simple like this I could drop in.
I expect that later on, there will be a whole “drop into cyberspace” system once the technomancer is released officially, but until then, the specific hacking rules and statblocks here will do. There are different types of computers discussed, how to set the stats, and a chart of sample vulnerabilities and countermeasures that you can slot in as needed.
Is it as robust as I'd hoped for when I heard it was coming initially? No. But it's what I expected it to be based on some playtest hacking hazards, which is so much better than simple “roll Computers—or Thievery if you're a Hacker” calls.
Conclusion and Rating
I guess the big question is whether or not it's worth picking up. And the answer is an unwavering yes. If you GM Starfinder, you're missing out on a lot if you don't grab this one. Between the lore for various places in the setting, tons of example hazards, afflictions, etc. that you can just slot in, and not having to adapt things from the Pathfinder GM Core anymore, it's the book I've been waiting on.
Do I wish that it had better starship and space combat in it? Yeah, I really do. But my party spends most of their time on the ground, and I tend to be a pretty dramatic guy, so the cinematic rules work well for us. At least for the moment. My biggest issue is not telling me how much various kinds of spaceships cost, and that's something that was handwaved in first edition, so I had just hoped 2e would do better on that.
In the end, the PDF of the GM Core has stayed open on all of my devices since I got it. I've referenced and cross-referenced, looked stuff up, CMD-F searched, and found an answer to pretty much every question I've had when running my weekly game. The SF2e GM Core is well-organized, easy to understand, and a perfect complement to the Player Core.