Traveller House Rules


These rules are intended to be compatible with Mongoose Publishing’s Traveller Core Rulebook and the System Reference Document available at


To provide an incentive to create younger, less-skilled player characters, PCs who take zero career terms may spend up to thirty points on skills and characteristics as per the point-buy rules on page 40; characters who take one term may spend 24, characters who take two terms may spend 18, and characters who take three terms may spend 12. Characteristics may be raised by spending the difference in point cost between the current and the desired score; eg, a Strength 7 score (point cost 2) may be raised to a Strength 10 (point cost 6) by the expenditure of four points. PCs without a Biotics characteristic may elect to purchase it with these points, starting from a base value of 6.


A character who rolls a skill advancement for a non-specialty skill they already possess at rank 4 may choose any other result from that table.


If a character fails their survival roll in a term, they are considered only to have spent 1d3+1 years in that term. This is intended to reduce the frequency of characters starting out at ages that are multiples of 4 plus eighteen.

Stealth and combat

To give Stealth an in-combat application, characters who have at least 3/4 cover from every current opponent may, as a minor action, make a Dexterity or Intelligence plus Stealth skill check to become Stealthed. Stealthed characters inflict a penalty equal to the Effect of the check to any ranged attackers.

Attacking from Stealth instantly reveals the character’s location to enemies – however, the Stealthed character receives a 2d6 damage benefit to the melee, ranged, or tech/biotic attack, and enemies attacked by Stealthed characters may not dodge or parry. This benefit does not apply to burst or full-auto fire, as it assumes the character has carefully lined up a single lethal shot.


To facilitate online play, rather than keeping strict track of PC and NPC positions on a gridded board, it will be assumed that the battlefield is broken up into a series of abstract “zones” of arbitrary size defined by who occupies them (one “zone” might encompass three nearby PCs, while another might encompass a PC and two enemies) and by the zones’ combat-relevant relationship to each other (zone A provides 50% cover against fire coming from zone B, zone B is at medium range from zone C and requires two move actions to reach, zone C is elevated above zone D and requires a climb check to reach, etc.). Occupants of a given zone are assumed to be at Close range from each other unless grappling, at which point they are considered to be at Personal range. Area effects (grenades, etc.) used within a zone will affect all occupants of that zone.


During the course of play, PCs will have ample opportunity to practice and refine their existing skills, as well as occasionally picking up new ones. This is accomplished in play through the accumulation of Achievements. An Achievement is a special task or challenge set by the GM and given a name and a bounty of experience points (XP) reflecting its difficulty. An example:

Achievement Condition Reward
Tactician Participate in a firefight while taking no damage. +2 XP

An Achievement is awarded the first time a character or the party fulfills its condition, but not any time thereafter. Per the example above, a character would not receive additional XP for surviving a second or third firefight without damage – only the first.

Some Achievements are Public, their conditions visible and known to the players beforehand. These tend to have more generic conditions that reflect the characters’ skills or luck, and more modest XP rewards. Other Achievements are Secret, their prerequisites known only to the GM; these reflect progress made in the campaign story, such as the apprehension of a villain or the discovery of an important secret, and often yield larger XP rewards. Some very rare and lucrative Secret Achievements are multi-part, with several conditions to be fulfilled.

Xp and advancement

It is generally assumed that characters who have taken up travelling are living more dangerous and exciting lives than they had been on their previous careers, and are thus exposed to and pick up new skills with more alacrity. This is reflected by the accrual of Experience Points earned through Achievements. Earned XP may be spent for the chance to randomly improve a PC’s Skills or to cash in lucrative Benefits by buying rolls on the tables below.

Combat Skill Package (8 XP per roll)

Roll Skill
1 Melee
2 Gunner
3 Gun Combat
4 Heavy Weapons
5 Medic
6 Battle Dress

Biotic Skill Package (10 XP per roll)

Roll Skill
1 Warp
2 Lift
3 Throw
4 Barrier
5 Levitate
6 Melee (biotic)

Technical Skill Package (6 XP per roll)

Roll Skill
1 Comms
2 Sensors
3 Computers
4 Engineer
5 Mechanic
6 Science (physical, life, social, space)

Planetary Skill Package (4 XP per roll)

Roll Skill
1 Navigation
2 Drive
3 Flyer
4 Seafaring
5 Streetwise
6 Broker

Space Skill Package (4 XP per roll)

Roll Skill
1 Comms
2 Sensors
3 Astrogation
4 Vacc Suit
5 Zero-G
6 Pilot

Interpersonal Skill Package (7 XP per roll)

Roll Skill
1 Advocate
2 Carouse
3 Diplomat
4 Deception
5 Persuade
6 Streetwise

Leadership Skill Package (6 XP per roll)

Roll Skill
1 Leadership
2 Medic
3 Recon
4 Tactics
5 Diplomacy
6 Investigate

Underworld Skill Package (6 XP per roll)

Roll Skill
1 Stealth
2 Streetwise
3 Deception
4 Gambler
5 Computers
6 Investigate

Basic Benefit Roll (2 XP per roll)

Roll Cash Benefit
1 2,000 Melee Weapon
2 4,000 Ranged Weapon
3 6,000 Combat Armour (75,000Cr or cheaper)
4 8,000 Ammo Mod
5 10,000 Weapon Mod or 1d3 Ship Shares
6 12,000 Armor Mod or 1d6 Ship Shares

Premium Benefit Roll (5 XP per roll)

Roll Cash Benefit
1 6,000 Upgrade a Contact to an Ally.
2 8,000 Skill Implant or 1d3 Ship Shares
3 10,000 Raise lowest Characteristic by 1.
4 16,000 +1 Edu or Soc
5 20,000 Combat Implant or +1 End
6 30,000 Omni-Tool or Biotic Amp, or 1d10 Ship Shares, or +2 Soc

Galaxy Map

Traveller House Rules

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