Sci-Fi Fifth Edition Rules Quickie Design Notes

I got a little burned out recently. When I get burned out, I don’t stop writing, I just write something different; like a palate cleanser, if you will. In this instance, I thought I might come up with some quickie science-fiction design notes, zip up some easy changes, and throw it all in a PDF.

After all, shouldn’t Fifth Edition have some science fiction by now?

The setting I’m thinking of is similar to Star Trek. Fly around in a ship (travel the world) with your crew (party), go on missions (adventures), and save the galaxy (world) from weird aliens (monsters).

How to make a science fiction game out of Fifth Edition rules?

All right, so there’s a little work to be done on the forefront. To figure out the stuff I’ll need to change, I’m just going to go chapter by chapter of the PHB, then look up the optional stuff in the back end of the DMG. Finally, I’m going to make notes on what sorts of monsters work from the MM.

Player’s Handbook Adjustments

Here are the changes that need to be made in the Player’s Handbook. Anything that I don’t mention, assume it’s fine the way it is. Naturally, this excludes any fluff that’s geared around fantasy settings.

Part 1 – Chapter 2: Races

Instead of creating all-new races (at least not yet), I think it’s a better idea to make adjustments to the existing ones so that it fits a sci-fi setting a lot better. And rename them, of course.


I need to change Dwarven Combat Training, Tool Proficiency, and Stonecunning features.

The Mountain Dwarves need something to replace Dwarven Armor Training.


High elves need something to replace Elf Weapon Training.

Cantrips are fine since I plan on making spells into psychic powers. I should probably drop the entire wood elf subclass, though.

Like high elves, drow will need adjustments to Drow Magic and Drow Weapon Training.


The forest gnome subclass probably needs to go, leaving rock gnome as the only choice.

The rock gnomes’ Tinker choice probably needs some options that fit the sci-fi flavor better.


Infernal Legacy needs to be clear that it’s psychic, but it is otherwise fine.

Part 1 – Chapter 3: Classes

The biggest overhaul will probably be with classes. It’s impossible to fully convert a lot of these options over to a sci-fi/Star Trek setting. When doing this, though, I don’t want to have to do a whole lot of work and create new classes. Therefore, I’m going to figure out what’s possible to keep first (that doesn’t require to overhaul a lot), what needs to be cut (too much work to keep), and then adjust accordingly.

Barbarian – Keep

Interestingly, this class might still work as it is. We all remember Worf raging out on TNG, right?

The armor and weapons proficiencies block will need to change, as will skills (but that’s in general). Obviously, equipment’s gotta change, too.

Unarmored defense is probably good to go, although armor is kinda weird in science fiction. But that’s more of a problem for the other classes.

Path of the Totem Warrior is a bit of a mess thematically, but I think some reskinning can make it work a little better. Spirit Walker will need to change, since commune with nature may not gel too well with the sci-fi theme.

Bard – Cut

I’d love to keep the bard and I think I could make enough changes to it thematically to do so, but the magic makes it too problematic. The changes I would need to make would essentially recreate the entire class. Sorry, bard fans, there’s no bards in space!

Cleric – Cut

Another one that I would love to keep, but it’s too hard to explain away so much of the way the class works. Plus, rewriting all those subs would be a nightmare. I’ll have to create a medical officer class to replace it since there always needs to be a healer/buff around.

Druid – Cut

Yeah, sorry. Bye-bye.

Fighter – Keep

The fighter is pretty basic, so it should be able to stay no problem. I’ll just have to make some pretty big changes. The armor proficiencies, equipment, etc. will have to change along with all the other equipment in the game, so that’s not a big deal.

Fighting Style will need some overhaul. Being a good shot is useful, obviously, and possibly dueling, but there’s not a lot of melee weapon combat in science-fiction (other than the occasional bat’leth, of course), so the fighter will need some replacement options. Either that or just give it a straight-up choice between “punching things real good” or “shooting things real good.”

Battlemaster probably won’t work at all as a subclass simply because I don’t foresee a lot of melee going down in this setting. It’s going to be pretty big on ranged with the occasional bout of fisticuffs.

Eldritch Knight can possibly stay, only because I plan on opening up a whole realm of psychic powers and 90% EK powers are abjuration and evocation. However, Eldritch Knight will probably need something in place of weapon bond.

Monk – Keep

Most of the martial classes naturally lend themselves to a science fiction game and monks are no different.

Equipment will need changing, of course.

The rest of the stuff seems fine. It’s okay to have one or two “weird” classes in science fiction and I think the monk fits that mold.

Paladin – Cut

Just too much to change with the paladin. Better just to create something else.

Ranger – Cut

The ranger suffers from the same issue as the paladin and druid. It’s gotta go.

Rogue – Keep

Rogue can stay. There are criminals in science fiction.

Armor and weapons will need to change.

Equipment’s gotta change.

The subclasses are mostly fine, although the Thieves’ Use Magic Device may not be as handy so that probably needs an adjustment. Maybe Use Alien Technology?

Sorcerer – Keep

Of the three arcane casting classes, I decided that sorcerer is probably the least “weird” of the bunch. So it gets to stay. However, it’s getting a heavy retheme as a psychic.

Gotta change equipment and proficiencies. Spellcasting will get a bunch of changes, and I’ll probably go to the Spell Points system from the DMG for it.

I’m not sure that either Sorcerous Origin from the PHB really works with what I’m going for. Instead, I think I’ll pick up Divine Soul (for the healing) and Shadow Magic from Xanathar’s.

Warlock – Cut

Warlock’s just got too much weird stuff going on with it (the class is kind of all over the place in general) that I’d just rather not mess with it.

Wizard – Possibly Keep

Finally, the wizard. I think the wizard could work, but possibly as a technologist/artificer type instead of a wizard. This is one I’ll need to stew on a little more. Like the others, though, it’d need a serious overhaul to do it.

Probably just better to create a whole new class.

Part 1 – Chapter 4: Personality and Background

Personality and background is kind of odd. Really, not a lot has to change and it can still keep with the theme. After all, just because you’re traveling around in space, doesn’t mean you can’t have humble origins.

The biggest overhaul is probably in the traits, ideals, bond, and flaw tables. Anything that doesn’t make sense thematically will have to go or get changed.

Beyond that, it’s just getting the themes down right.

Part 1 – Chapter 5: Equipment

Here comes hell. Haha! Equipment will probably get one of the biggest overhauls of all. After all, none of this stuff really works in science fiction.

Wealth will need to be “credits” or something similar.

Armor needs a big fat thematic shift. Can’t go wearing plate in space, eh?

Definitely no need for all the melee weapons. Ranged weapons gotta split, too. Going to have to bring in some stuff from the DMG.

Who needs adventuring gear when you have a freakin’ spaceship?

Anyways, no point in going through any more of this. I just have to rewrite the whole chapter.

Part 1 – Chapter 6: Customization Options

Feats will need some love since a lot are tied to fantasy elements. Otherwise, everything else here is cool.

Part 2 – Chapter 7: Using Ability Scores

Some of the skills need retheming. And I’m not sure Animal Handling has any real use in space, so that might have to totally go. It’s probably better to bump up some ship-piloting skills in its place, but not so much using Wisdom as its basis.

Part 2 – Chapter 8: Adventuring

It’s not so much that the stuff in this chapter doesn’t work in a fantasy setting, it’s that it’s probably missing a lot of what’s important to science-fiction: namely ship travel, teleportation devices, etc. I’ll have to write all that in.

Part 2 – Chapter 9: Combat

Combat is probably fine, although ship-to-ship combat will probably need to be determined. It’s too bad Saltmarsh isn’t out yet, which is supposed to have a lot of the nautical stuff in it.

Part 3 – Chapter 10: Spellcasting

The mechanics themselves of spellcasting can stay, although I plan on making it mostly about psychic powers instead of actual magic. Components are kind funky with psychic powers so I may have to strip some of those out.

Part 3 – Chapter 11: Spells

I don’t want to make too many major changes, but a lot of the spells found here will probably just get the boot. I’ll just download a spreadsheet somewhere and cross out the ones that don’t make sense.

Keep in mind, too, that technology will be able to replace a lot of these effects. The future is magical, yo!

Dungeon Master’s Guide Inclusions

Unlike the Player’s Handbook, The Dungeon Master’s Guide is less about changing and stripping unnecessary elements, but figuring out the optional rules that should be tossed in. Also, there will need to be some rough rules for campaign creating since space operates differently than a fantasy setting.

Here is a quick checklist of the stuff I plan on porting from the first two parts of the DMG:

  1. The Mapping Your Campaign section in Chapter 1 is important, but it’s less about provinces, kingdoms, and continents, and more about galaxies, planets, and ships.
  2. Settlements exist but are quite different thanks to technology.
  3. While the planes aren’t important, different regions of space could be a big deal. Plus, there can be planets that duplicate the effect of planes.
  4. All of the adventure creation stuff and NPC stuff is pretty good to go. Just needs some thematic changes. Science fiction–especially stuff in the Star Trek mold–is way less about location-based adventures, and more about event-based stuff, bouncing from place to place, solving mysteries, etc.
  5. Adventure Environments, of course, need a pretty big overhaul. It’s important, nonetheless.
  6. Wilderness Survival still makes sense. In fact, strange planets are likely to have even more extreme conditions.
  7. There probably needs to be some rules on zero gravity movement. I can probably borrow from the swimming rules for that.
  8. The rules for ships are incredibly important for science fiction and definitely, need to be expanded upon. A simple stat line on a table won’t do. Ships will serve multiple purposes, too.
  9. There should still be downtime activities but mostly geared toward science fiction staples.
  10. Treasure doesn’t really have the same importance in a sci-fi setting as it does in a fantasy setting, although, there are plenty of missions in science fiction that involve earning money, finding artifacts, etc.
  11. Most of the stuff in chapter 8 should stay. It’s pretty relevant no matter what the setting and it is built off the core engine of Fifth Edition.
  12. Siege equipment gives me an outline for how ship weaponry should work, as do the chapters on sea/air vessels and object AC/hp.
  13. In chapter 9, futuristic items are introduced. These are great models but tend to be a little on the overpowered side. For example, a laser pistol does 3d6 radiant damage. Toss in a dex bonus, and that’s a whole lot of damage for a 1st-level character. I can either adjust these or adjust CRs. I think I’ll just adjust these so they fit better with the basic ranged weapons from the PHB. For example, a basic laser rifle does the same damage that a longbow does, etc. No need to go nuts.

Monster Manual Keep, Cut, and Adjust

Finally, the Monster Manual. Instead of going monster-by-monster, I instead will take a look at the monster types and make notes on how I’d need to change each of them.

There’s a lot of stuff in the Monster Manual that works just the way it is. All you need to do is rename and retheme a bit.


Of all the monster types, aberrations probably lend themselves best to Star Trek/science fiction settings. They’re all weird and tentacle-y.


Interestingly, it’s less likely that you’ll run into traditional beasts in a science-fiction setting. There’s not a whole lot of horses running around on space ships.


I’d use these sparingly, as they will quickly pull the PC’s out of the sci-fi element. Certainly, Star Trek and Star Wars have their share of religious themes, but you don’t want to go over the top with this kinda thing (unless that’s what you’re going for).


The trouble with the constructs in the MM is that most of them are tied to fantasy settings. Animated stuff is too magical and whimsical for a science-fiction setting. Iron golems, too, have a specific dynamic that’s very D&D. There are some exceptions, though: Modrons are perfect as weird little robo-aliens.

Now, when it comes to creating new monsters for a science-fiction setting, constructs can definitely use some love. Killer robots!


Like celestials, dragons are a little too fantasy to have a comfortable place in a science-fiction setting. Use them sparingly.


These could be fun. In Star Trek, Doctor Who, and other high-concept science-fiction shows, the heroes would often battle rock monsters, fire monsters, and other things like that on alien planets. Imagine mephits as an alien race!


Fey scream fantasy, so be sure to try to reskin them as much as possible.


Fiends can work, but like celestials and dragons, are probably best used very little. They tend to be pretty powerful, too, so that’s something else to consider.


Giant can work, but space ships tend to be crowded spaces. Like humanoids, they will need to have adjustments to weapons and armor to fit into the science fiction setting.


Here is where the majority of the good stuff will come from. All the weird races in the Monster Manual can be changed to science fiction races. You will have to swap out their weapons and arms for advanced stuff (unless you want to make them primitive, of course). And they could probably use some name changes, too, just so it doesn’t seem too fantasy. For example, you could easily turn an orc into an ogzod, make its greataxe more like a bat’lef, and give it a laser rifle. Pew pew!


Another good spot for monsters, monstrosities offer up lots of cool critters and the occasional pseudo-humanoid like the doppelganger that can fit comfortably into a science fiction setting.


Oh yeah, oozes totally work. Something’s gotta eat those red shirts on that barren planet.


Weird plant species on planets? Yep!


Undead kinda falls into that “probably too fantasy” category to really work, too. The occasional ghost or even a space vampire may not be too bad, but don’t overdo it.


The NPC index, of course, will probably need to be totally stripped and reworked for NPCs that make more sense in a science fiction setting.


Next Up: Putting It All Together

Well, those are most of my notes that will serve as a reference for all this material. Now it’s just a matter of gluing it all together to it makes sense. Overall, I’m pretty satisfied with my notes as I only see a few major things that I’ll have to create.

Follow along with the blog to see more get made!

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Art by Shutterstock (used with permission).


1 thought on “Sci-Fi Fifth Edition Rules Quickie Design Notes

  1. Fantastic that you are so idea filled and prolific that you are an endless wellspring. Never having looked at myself as a creator in myself since becoming a gamer but now I do and you are one of my many new inspirations. This being my first comment I had to give you props.

    As for the topic, in the theme of your cleric idea, Rangers could be scouts as exploring the new and dangerous frontiers of worlds (if that is part of focus)
    Druids become Xenobiologists?
    Addressing magic as Psionics, Mages (Psionicists) totally rock with the focus we normally attribute to monks
    Clerics, Paladins, Warlocks..with psionics replacing magic, these folks could tap into beings from other dimensions or higher powers as we think of their dieties and patrons or those ideas are just a focus for their interactions with psionics? Just like the mystical powers of the monk.

    I’m a big person about reskinning rather than redoing/tweaking/recreating as you and am excited to see where you go with this. If I can afford it I want to become a patron as I realize I definitely am a fan of what you do as a creative. And with such class👍🏽

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