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This campaign mostly uses d20, d20 Modern, and d20 Future rules, with some Traveller20 stirred in, and lots of universe-specific additions and subtractions related to races, classes, skills, etc.

When there’s a significant departure from d20 rules, I’ll try to make note of it here.

Automatic Weapons

Featuring a few common tweaks to the D20 Modern rules, because the original rules are conspicuously unrealistic and stupid.

  • If a ranged weapon has an automatic rate of fire, a character may set it on autofire.
  • Autofire on a longarm fires ten bullets, or if there are less than ten rounds left in the chamber, it fires all remaining rounds. The latter situation occurs, adjust rolls below accordingly (substituting 10 bullets for appropriate number). A submachine gun fires only five bullets in automatic mode; when using SMGs, make adjustments to the numbers below accordingly.
  • Autofire is not the same thing as Burst Fire, which involves firing a short burst at a specific target. Firing a burst requires the Burst Fire feat.
  • Autofire affects an area and everyone in it, not a specific creature.
  • The character targets a 10-foot-by-10-foot area and makes an attack roll; the targeted area has an effective Defense of 10. (If the character does not have the Advanced Firearms Proficiency feat, he or she takes a –4 penalty on the attack roll.)
  • If the attack succeeds, every creature within the affected area must make a Reflex save (DC = original attack roll)
  • If the Reflex save is successful, the target creature avoids all damage.
  • If the target’s Reflex save fails, the creature(s) is/are hit. With multiple targets, use a sensible method to divide the 10 bullets between all targets within the area; which creature’s vicinity bullets are flying toward. (A fair but ponderous method: hit players roll against each other ten times; each loss means one bullet is coming in that creature’s direction. Open to finding and using a faster, fair method, if situation allows).
  • Each hit character rolls 1d10 (or number of incoming bullets in the case of multiple characters) to see how many bullets strike him or her. Total hits cannot exceed 10. Still need to work on the a mechanic for reducing hits in this scenario (possibly: when 10 is exceeded, start removing one hit at a time, alternating between hit players until total reaches 10).
  • Attacker rolls damage for each hit player: [(number of hits) d (weapon damage die; 4/6/8/10)].
  • If the attack affects a character’s WP (i.e., critical hit, or VP are gone), wearing appropriate armor offers Damage Reduction. Mark’s hit location die would be great for this; otherwise, for each hit, roll 1d6 with 3 (or 3 & 4) counting as a chest hit. A chest hit lets worn armor give DR against that hit; +1 DR for each level of armor’s defense. With the overall philosophy of VP/WP, this mechanic might not be necessary.


I keep losing my shotgun rules, so here they are for reference.

  • Unlike automatic weapons, shotguns fire at an individual target.
  • Shotguns deliver d6(d4) damage, depending on type.
  • Example: Bob shoots at Mr. Bugbear with a shotgun. He rolls a 4 for the d6 shots that hit the bugbear, signifying that 4 pellets hit him. He then takes 4 d4 and rolls to see how much damage they do. Of that, he does 1, 2, 1, and 4 damage. The bugbear takes 8 damage.
  • Optional Damage Resistance: if an attack affects the target’s WP (critical hit, or VP depleted), roll Mark’s body hit location die (or 1d6, with 3 [3 & 4?] being a chest hit); on each chest hit, target gets +1 DR for each level of armor protection. With the overall philosophy of VP/WP, this mechanic might not be necessary.

Another Free Feat

In case I forgot to mention this. Please gift yourself with the Basic Firearms Proficiency feat. Life is rough on the tradelanes; you’d be hard pressed to find a Terran, Ambyloid, or Murdi who hasn’t long possessed a basic knowledge of common firearms.


Grappling. No rule changes; just posting them where they’ll be close at hand, and in an easy to read format.

Tentative rule: Maximum HP gain at level-up

I’m open to other alternatives—a flat HP bonus, or adopting some 4e rules—but until we get the details worked out, I’m okay with characters just taking their maximum possible HP at level up. I’d rather have a character take 8 HP than roll 1d8 and end up with 1 HP. Future combat is already deadly enough without a single bad roll permanently gimping your characters.

Accelerated Leveling

I’d like to try awarding and tracking XP a little more fastidiously than we normally do. However, classes get a whole lot more interesting at 3rd or 4th level, so I’ll probably throw in a beefy XP multiplier for the first couple sessions, just to get us rolling.

How’s this for accelerated? BOOM YOU’RE THIRD LEVEL!

Action Points

In addition to standard starting and level-up bonuses, Action Points will recharge at a rate of one per adventure, up to your character’s max (5 + half level). Remember, Action Points are less powerful here than in 4th Edition, but you get more and they can have some pretty neat affects on gameplay. Rather than the nervous hoarding that the vanilla AP-awarding mechanic promotes, I want players to feel comfortably burning an AP or two when it might help some everyday situation.


At some point, in such a tech-heavy universe, crafting could present some interesting gameplay/story possibilities. However, I’ve always thought pinning an XP cost to item crafting is the dumbest damned thing, and I’ll have none of it! Unless you’re crocheting your soul into a Dire Doomsday Doily of Dimensional Destruction, crafting will work just like it does in real life: taking skill, time, and tangible resources (money, materials, etc.).

Create Two Characters

See my explanation on the Character Creation page.

Take This Feat, Please

To represent the ubiquity of basic starship know-how on the tradelanes, during character creation, please select one free bonus feat from the following list. Incidentally, you might check out Character Creation (if you haven’t already) for my rambling advice on what sorts of starship-related roles you might want your characters to fill. Note: you will need to meet the skill prereqs for whatever feat you pick.

  • Gearhead (good for engineer types)
  • Medical Expert (sickbays on most ships; young docs and medics quickly hone their trade)
  • Salvage (another for engineer types)
  • Spacer (decent misc. crew feat)
  • Starship Gunnery (a must for gunners)
  • Starship Operation (a must for pilots)
  • Zero-G Training (will no doubt happen at some point; if nothing else on the list appeals to you)

Feat Tweak: Starship Operation

I’m tweaking the Starship Operation feat so it’s not petty in its specificity. When taking this feat and selecting ship type, don’t pick a single ship size. Choose either 1.) Ultralight, Light, and Mediumweight, or 2.) Mediumweight, Heavy, and Superheavy. I highly recommend the former for this campaign; you’ll get a whole lot more mileage out of being able to fly smaller, common ships.

Alternate Facing/Flanking Mechanic

This is one of two popular d20 alternate rules that you might end up hating, but I really love the concept. If it completely sucks and bogs down combat we can drop it, but I have a feeling it will make gunplay tactics more exciting. It’s an easy and flexible mechanic. Basically, the direction you’re facing matters. Someone holed up in cover? Work with your team and execute a little flanking/pincer maneuver; one of you is likely to get a well-bonused shot to the enemy’s backside. Because flanking bonuses are now the result of, well… actual flanking, instead of the weirdo rule where you have to envelop your enemy into a precisely aligned spooning threesome.

For a complete explanation of this mechanic, look here.

Vitality and Wound Points

Here’s the other popular alternate rule I’d like to try, as long as nobody immediately flips the table over in anger. Vitality and Wound points are a slightly different take on the Hit Points system. It’s got a nice sense of realism to it, and seems to be really nicely suited to a low-magic (low-healing), ranged-heavy campaign.

The concept:

“Vitality points are a measure of a character’s ability to turn a direct hit into a graze or a glancing blow with no serious consequences.” You acquire these in the same way as hit points; unless I’m forgetting or misreading something, your VP will always be the same what your HP would have been (class-dependent increase each level, plus CON mod).

“Wound points measure how much true physical damage a character can withstand. Damage reduces wound points only after all vitality points are gone, or when a character is struck by a critical hit.” Your max WP is equal to your CON score (not bonus).

To me, it’s much more evocative to imagine a hero burning through Vitality Points as he just barely dodges gunfire and turns would-be kill-shots into grazes. But soon he tires, his luck is running out, and then BOOM all the sudden he takes a serious, life-threatening Wound. And then another. He crawls into cover, thoroughly messed up… Bleeding everywhere, hands shaking… Either some back-up or a really amazing turn of luck had better show up soon.

So cinematic!

With HP, they same scenario seems much less compelling. “BOOM he got shot, and BOOM he got shot again, and BOOM he got shot again, and—uh oh, he’s ‘bloodied’ now—BOOM he got shot again, and BOOM ooooh this last shot did the same amount of damage as the others, but it’s collectively just all too much! Goodbye world!”

For a complete explanation of the VP/WP mechanic, look here.

Starship Combat

See Starships to browse the still-evolving rules-in-progress for starship combat.

Here are a few of the more noticeable rule changes:

  • Shifting to ship-scale combat will also mean a shift from squares to hexes.
  • Facing rules and firing arcs will apply (when applicable).
  • Ideally, every crew member will have something interesting to do during combat.
  • Combat happens in 30-second rounds (instead of 6). Each round is divided into two parts: the Movement Phase and the Firing Phase.
  • A modified initiative roll is made by each Commander every round. The winner’s ship moves last (offering a major tactical advantage), but fires first.
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