Conversion Rules

Conversion rules

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

Some of the race modifications and travel rules are courtesy of the poster MalaDicta on the forums.



Automatically roll for Bio, +1 Dex, +1 Soc, -1 Str, -1 End. The Long View: Asari begin at age 100, and career terms represent twenty-year intervals rather than four-year ones; Asari who fail survival rolls are assumed to have spent 2 + 3d6 years in that term. Asari do not begin making aging rolls until the age of 220, and may ignore age-related penalties for entering careers (but not term-related ones). All advancement rolls suffer a -2 DM.


+1 Str, +1 End, +1 Int, -1 Edu, -2 Soc (unless among other Batarians).


Automatically roll for Bio, +1 Str, +1 Dex, -2 End. The Compact: Drell player characters begin with a Hanar contact.


May choose to roll for Bio. A New Breed: Humans who roll for Biotic scores are limited to a maximum of 4 career terms.


+2 Str, +2 End, -2 Int, -2 Edu, -2 Soc (unless intimidating someone, in which case +2). At character creation, a Krogan may trade their +2 End bonus for the ability to roll a Biotic score. Krogan begin at age 20 and career terms represent twenty-year intervals rather than four-year ones; Krogan who fail survival rolls are assumed to have spent 2 + 3d6 years in that term. Life of Violence: Krogan do not make aging rolls, and may ignore age-related penalties for entering careers (but not term-related ones), but must use the optional “Iron Man” system on page 40; if they fail a survival roll, the character is dead.


+1 Int, +1 Edu, -2 End, -2 Soc (unless around other Quarians). Always begin with Vacc Suit 1. Pilgrimage: Quarians must take Drifter for their first term, but receive a +2 DM for that survival roll.


-2 Str, -2 End, +2 Int, +2 Edu. Rapid Metabolism: Salarian PCs roll twice on skill tables for each career term, but begin making aging rolls after the second term at 2d6-5.


Automatically roll for Bio, -1 Dex, +1 End. Team Spirit: Turian characters must take Agent (law enforcement or intelligence), Army, Marines, or Navy for their first term. All Turian player characters begin with a Turian contact.


While Biotics – abilities that allow the mental manipulation of mass effect fields – exist, actual “psionics” do not. The sole exception is Asari “joining,” a quasi-telepathic process which is limited to skin contact, requires the conscious consent of both parties, and conveys gestalt impressions, physical stimuli, and emotional states rather than detailed information. Since joining has no combat or conflict-resolution applications, there are no game rules attached to it.


FTL spaceships use the Warp Drive variant rules on page 109 for intra-cluster travel. Commercial craft are powered by fusion or cheap fission engines, while military craft use antimatter.

Travel between star clusters or across galactic distances employs Mass Relays. Mass Relay travel is effectively instantaneous and requires no special power source or space drive, as the Relays themselves do the work. Relay travel is accomplished by making a standard-difficulty Astrogation check to plot a course, a routine Communications check to transmit that course to the Relay, and a standard Piloting check to move into position.

Skills and Specialties

The vast majority of Traveller skills are represented in Mass Effect; the following list covers the very few exceptions.

Art has a new specialty, Art (cooking), representing the character’s ability to cook tasty and nourishing food for several species.
Engineer (Jump Drive) is now Engineer (FTL Drive) and refers to the operation and maintenance of a ship’s mass effect fields and Element Zero core.
Gun Combat (Energy Rifle) and (Energy Pistol) do not exist, as energy and laser weapons are not a significant factor in Mass Effect.
The Language skill has the following specialties: Asari Dialects, Batarian Dialects, Drell Dialects, Elcor Body Language, Geth Binary, Hanar Bioluminescence, Human Dialects, Krogan Dialects, Quarian Dialects, Salarian Dialects, Turian Dialects, and Written Prothean.
Life Sciences (Psionicology) is now Life Sciences (Biotics).
Space Sciences has a new specialty, Space Sciences (Mass Effect), which represents study of the exotic Element Zero and its uses.
The Steward skill does not exist. Characters who receive it during creation may re-roll that skill roll.


Medigel requires a combat action to use and heals 3 characteristic points plus 1 for every rank in Medic (including rank 0), divided however the receiving character wishes. Example: Sandra uses Medigel on Victus. Sandra has Medic 2, so the Medigel heals six characteristic points.

Omni-Tools and Biotic Amps are required to activate Tech and Biotic abilities respectively. Omni-Tools must be earned during character creation or purchased with credits; characters with Biotics training are assumed to possess amps at the start of play, but in the rare event that a character develops biotic powers in the course of play, they will have to undergo the costly surgery to install a biotic amp before they may access these powers. Rare, high-quality amps and tools are known to exist and may confer special benefits, such as DM bonuses to attacks or discounts on power point usage.

Armor and Shields

Much of the effectiveness of armor derives from the kinetic barriers (“shields”) it generates. Therefore, all protective gear has two listed protection values – Armor and Shields – and the sum of these two values is the armor’s base damage resistance. Every successful ranged attack reduces the Shield value by 1, to a minimum of 0; if the defender spends two consecutive minor actions in cover and is not hit by further fire, the barrier capacitor recharges and the Shield value returns to its maximum.

Shield strength is not counted when defending against melee attacks. Be on guard against charging Krogan!

The vast majority of armor worn in Mass Effect is Combat Armor of one level or another. Battle Dress is extremely rare and experimental. All Combat Armors come equipped with Eye Protection, Magnetic Grapples, and TL 11 Computer Weave.

Ablative Armor and Reflective Armor do not exist as laser weapons are not a significant factor in most of the Mass Effect universe.

Weapons ammo and mods

The overwhelming majority of firearms in Mass Effect are slug throwers that function as Pistols, Autopistols, Shotguns or ACRs. Sniper Rifles are available; their statlines are detailed in Weapons and Armor and their relevant skill is Gun Combat (sniper rifle). They feature a new Ranged (sniper) range classification:

Weapon Personal Close Short Medium Long Very Long Distant
Sniper -3 -2 -1 +0 +1 +0 -1

Some exotic energy weapons, such as Collector Lasers and Geth Plasma Shotguns, do exist, but are not available for purchase and are unlikely to be encountered by most PCs.

Most slugthrowers in Mass Effect have effectively unlimited ammunition; the Magazine value is a measure of the number of shots a gun may fire in a combat before it must cool (the user may elect to not fire that weapon for a full round, perhaps using a skill or a second sidearm; alternatively, the user may spend a minor action to actively vent a portion of the weapon’s coolant, swapping in a new “thermal clip”).

All Traveller melee weapons are available in Mass Effect.

Some Traveller heavy weapons are available in Mass Effect, but have been reflavored somewhat; to supplement them, an assortment of new heavy weapons has been created to model the choices available in the Mass Effect games. PGMPs and FGMPs do not exist, as such, but their statlines may be used to represent exotic or rare heavy weaponry such as Geth armature plasma cannons.

All weapons and armors have “slots” to accommodate various off-the-shelf optional modifications. Most have two slots; some more specialized or rare items have one or none, while commonplace gear may feature as many as three. Modifications encompass the choices listed on pages 89 and 102 as well as other, more setting-specific options detailed in Weapons and Armor.

Benefit rolls

Ship Shares: If the game being played does not accommodate a mortgaged ship, characters who roll a Ship Shares result may opt to receive the equivalent of that roll on the Cash table instead, even if their three Cash rolls have been used. For variable values of Ship Shares (1d3 Ship Shares, etc.) the character receives that cash value multiplied by the variable number.

Weapon or Scientific Equipment: Characters who roll either of these results may opt, one time, to take a Bio-Amp upgrade or a basic Omni-Tool.

Ally in the Imperium: The PC receives an ally involved in some way in the Citadel Council.

Travellers’ Aid Society: Since the Travellers’ Aid Society does not exist in the Mass Effect galaxy, PCs are instead considered to receive the benefits of TAS membership by earning favor with the mysterious Shadow Broker. The Broker always pays his debts and PCs who have, wittingly or unwittingly, earned Shadow Broker’s Favor find it easier to obtain lodgings in Class A and B starports and receive a marker from the Broker’s agents once every two months. This non-transferable marker – which may take the form of privileged insider information, a valuable resource, or one-time access to a contact – may be redeemed to gain a +3 DM to one Diplomat, Deception, Investigate, Persuade, Streetwise, Broker, or Carouse roll, or to add or subtract one from the result of any experience point roll.

Conversion Rules

Mass Effect: A Shattered Galaxy kdowell2 kdowell2