Gamemaster’s Guidepost: Unusual Background, Revisited

I’ve covered this before, but I felt it was a worthy topic to return to. This time, focusing on the GM. As a GM when exactly do you use a Unusual Background? Though I personally found the trait rather intuitive, many GMs seem to be mystified enough to just ignore it – which I think is a mistake. Done right, Unusual Background can add flavor and depth to your campaigns. First, you need to determine everything you’re going to allow into your campaign which is largely determined by what kind of setting your detailing as well as it’s genre. Are you allowing Exotic or Supernatural traits? Which ones? Are their any limitations? Can they only be purchased with a Power Modifier? Are they allowed as “wild” traits? Are certain abilities available, but rare? The Trait Sorter can be useful, but you’ll need to add some of the (few) traits they’ve added since the Basic Set once you’re done with that list. Decide which off-list abilities you’ll allow with a Unusual Background. For example, in a Space Opera game no Exotic or Supernatural trait may be taken without the Psionic Power Modifier or as a part of a Racial Template – but the GM decides that since many of the races in his campaign can interbreed with each other that leveled Unusual Background (Hybrid) trait is available. Each level costs 5 points and allows a character to possess a trait from any racial template other than his own.

The question of rarity is a bit more complicated. How do you, as a GM, determine what is rare in your campaign? The quickest method is to use the 50-10-0 method from GURPS Supers. Is it really rare? As in maybe 200 people on a planet have such capabilities? Then it’s a Unusual Background worth 50 points. Is it uncommon? You can only find people with such capabilities in even the smallest of cities? Then it’s a Unusual Background worth 10 points. Anything more isn’t worth points. Also, if you don’t have GURPS Psionic Campaigns – you should really get it, even if you don’t run games with psionic powers it has a lot of good advice on how to run games with powers in them. The box Unusual Background (Psi) is especially enlightening (see p. 13 of that book). A method which I’ve used in the past uses the Size and Speed/Range Table (p. B550); it’s quite handy! I also like using Eric B. Smith’s Extended Chart.

  1. Figure the total population of your campaign setting or its referred area. For example, if you’re campaign is set in “modern-day Earth,” then this would be around 7 billion.
  2. Next, determine the ratio of those with the ability to those without it. For example, if it were literally one in a million, the ratio would be 1:1,000,000
  3. Next, divide the ratio into the population. In that same example, it would be: 7,000,000,000 / 1,000,000 or 7,000 people worldwide.
  4. Next, read over the Linear Measurement chart on the Speed/Range Table and then read across to the Speed/Range column, this number is the cost of the Unusual Background to possess that rare capability. Continuing our example, this would be a trait worth 21 points.
  5. Finally, depending on what exactly the ability is, use the following modifiers to determine the final cost:
    • Multiple abilities or access to a entire Power Source (e.g., psionic abilities): round the cost up to the nearest multiple of five.
    • Ability is very rare (most people are “latents;” at least 50%) or unknown (there are few, if any countermeasures against it that are available to the public): add 5 to the final cost if one or the other or 10 if both.
    • Ability is well known or countermeasures are widely available: divide final cost by 2.Use this modifier after all others; this is incompatible with the unknown modifier (see above).

Example: In the GM’s Scorched Earth campaign, he decides that psionic abilities and beneficial mutations may be possible outside of the Pskyer and Mutate racial templates – but they’ll be pretty rare. After the Storm hit and wiped out most of the population of the planet, only 2,000,000,000 people remain worldwide. The GM decides that 1:400,000 possess either a singular psionic ability or beneficial mutation and. Additionally, countermeasures are widely available since everyone knows about psi powers and biological mutations.  Thus possessing either in his campaign is a 10-point Unusual Background.

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  1. I think – I could be wrong, but this is where I am coming at this from – that UB is misunderstood because there is a default assumption that the points associated with an ability are already there to ensure a relative level of utility. When you add an UB to the situation you're in essence saying "in my campaign these cost more, under certain circumstances" which runs counter to the notion that someone who is more intimate with the system has already balanced these gifts against one another.

    Also, beware the player who thinks UB is his get out of jail free card for playing an anime ninja in your western european style fantasy game. Some will see it as a way to "get their way" instead of a GM tool at all.

  2. Yes. that IS part of it. Agreed fully. As for the ninja-player – Unusual Background, like all traits are subject to GM purview. He absolutely has the right to say "No. That's just not possible, sorry, come up with a new concept."

  3. The question of rarity is a bit more complicated. How do you, as a GM, determine what is rare in your campaign? The quickest method is to use the 50-10-0 method from GURPS Supers. Is it really rare? As in maybe 200 people on a planet have such capabilities? Then it's a Unusual Background worth 50 points. Is it uncommon?….

    I fundamentally disagree with this. IDHMBWM, but I also think that there are RAW that also differ.

    Unusual Background like all advantages is all about the utility it gives. Or it should be at least.

    Only son on planet of aliens great, thats a mix of a lot of things, maybe there is a perk level of UB maybe not, but its a whole mix of other advantages/disadvantages.

    Now the access to advantages (potentially disadvanteges too… which is an intersting thought) it gives you is the issue. And only I would argue in relation to the other PCs (potentially some NPCs too). So if we are all the only aliens on the planet thats 0 points as a UB. Just set the campaign point level to account for that.

    A one point of damage ranged attack in a campaign where the other PCs have liberal access to firearms? Maybe its a low level UB even if the PC is the only person on the planet with the ability.

    A healing power in a gritty campaign where healing normally takes time. Maybe all the PCs need to take a UB cause they are buying a way to short circuit your plot. And if they refuse access to the healing then they dont pay for the UB.

    And so on…

  4. Me personally? I literally figure out the odds of having if having a specific trait/power. If Chi Powers are possessed by a handful of people in a leaky boat who are about to save the world – then being one of those people is an Unusual Background, IF other player characters do not have those powers either. If all player characters have access to the same tier of ability, no matter how rare – then this isn't an Unusual Background – this is a campaign feature (not a setting feature – that's different). Basically, every player character "gets" that Unusual Background and there is no need to record it. No, in past campaigns I have said, "Everyone gets X points to create a character; you have access to W traits and Y powers. If you don't want access to those, then you get Z extra points to build your character." I used the weird trait in the post, and I probably should have just gone with my instinct and said "power" because people are getting hung up on it – thought it bears looking at as well. If no one in the campaign has 3D Spatial Sense except those with a rare gene, then that might be an Unusual Background. Maybe you get to join the Navigator's Guild or sell your services as an astrogator to the highest bidder. Either way, you have an advantage that normal characters don't.

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