House Rules


Any book is allowed by default, though any material may be banned at any time by the GM.

The following books are recommended:

Basic Set, Bio-Tech High-Tech, Martial Arts, Powers, Power-Ups 2, Social Engineering, Tactical Shooting, Ultra-Tech.

Additionally, material from Pyramid may be allowed, but must be approved first.

Optional Rules in Use

The following optional rules from materials published by SJ Games are in use. The source material(s) and page(s) in question are indicated in parantheses.

  • “Thinking Machines” additional detail for ultra-tech computing. Replaces Ultra-Tech rules. (Pyramid #3/37 – Techs and Toys II, p. 16-21)
  • “Do-or-Die Bullet Dodging”, requiring statement of defense in response to gunfire prior to the attack role, along with He Who Hesitates, representing a miss by 1 or 2 during an Attack or Defensive Attack as hesitation, resulting in no unready, lost ammo or similar. (Pyramid #3/34 – Alternate GURPS, p. 26-27)
  • “The Last Gasp” expanded Fatigue rules. (Pyramid #3/44 – Alternate GURPS II, p. 4-13)
  • “Realistic Injury” rules for hit locations and wounds, combined with the Low Tech split of the Torso into Chest and Abdomen, the latter including the ‘Groin’ location. (Low Tech, p. 102-103, Martial Arts, p. 136-139.)
  • Tactical Shooting. The whole shebang.
  • Similarly for Bio-Tech. Getting shot is inadvisable.

House Rules

Rules may be added to, or removed from, this list at any time.

  • Stats are restricted to 15 without an unusual background.
  • Per and Will must be purchased separately from IQ.
  • Gravity actually affects projectile weapons. So does atmospheric drag. Weapons listed on this site will already be adjusted, but the ones in the books aren’t. For everyone’s sanity, adjust the following:
    • Maximum range is always equal to the normal maximum range divided by 1.3. Write this in place of the usual max range on your sheet.
    • 1/2D range is equal to the normal 1/2D range divided by 1.7. This applies in environments that haven’t been artificially regulated. Note this adjusted range on your character sheet, but note the standard range in a paranthesis.
  • To avoid having the first the best lunatic with a knife kill y’all, we’ll be using Douglas Cole’s adjusted muscle-powered weapon damage.
  • The Targeted Attack technique also requires specialization by body type. A mindworm and a human do not share many common traits, for instance.

Things That Are Stated Outright In The Books, But Which Everyone Will Have Forgotten

  • Planet has 130% of Earth’s gravity. This has a few inconvenient side effects:
    • Encumbrance: Your total carried weight is ((CharWeight+EquipmentWeight)*0.3+EquipmentWeight). That means a 150 pound man wearing 30 pounds of gear will be carrying the equivalent of 84 pounds of gear. That makes a difference.
    • Jumping, Throwing:Distance jumped/thrown is divided by 1.3.
    • Falling: Due to the dense atmosphere, the terminal velocity is 0.87 times the original. On the other hand, you also accelerate faster, so falling is still a bad idea: Falling 4 yards onto a hard surface can bring you to 0 HP if you’re unlucky, and 8 yards will, more than half the time.
    • Stat Penalty: Isn’t applied. You’ve all grown up on planet, and are probably rather used to things there.
  • Planet has a Very Dense (Inert Gases, Low Oxygen) atmosphere. This means:
    • You get -1 HT if you’re not in a pressure-regulated area.
    • You get Tipsy, then Drunk, then Euphoric, due to inert-gas narcosis, if breathing the atmosphere.
    • You will lose fatigue at double rate while breathing the atmosphere. Anyone collapsing from lack of FPs will start suffocating.

House Rules

Alpha Centauri: Open Skies, Hidden Depths Moonstruck