Converting NPCs from AD&D to GURPS
 

I know I tend to do more work then is really necessary, but for my perpetually in the works Birthright game I am trying to establish a metric for converting NPCs.

I originally thought to simply port over the stats. I.e. 12 strength = 12 strength. But I suspect the upper ends are different. In AD&D a Dex of 18 is remarkable, but in GURPS it is almost stupidly dexterous making the NPC mindblowingly talented at every dex based skill.

So here is what I am thinking. Ability scores 2-14 convert at a one to one ratio, scores 15-16 lose one point in the conversion, and scores of 17-18 lose two points in the conversion.

Charisma scores relative to IQ along with concept will inform whether to add GURPS Charisma (an how much). Wisdom relative to Intelligence along with concept will inform me if I should provide bumps (or reductions) to Per and Will.

HT will be capped at 14 unless there is a good reason to do something else.

What do you think? I could scrap direct conversion all together, and build everyone up from concept, but I don't think that will be necessary. Can I have your thoughts?

Re: Converting NPCs from AD&D to GURPS
 

I would convert 10 to 12 straight and drop one point for 13 to 15 and two for 16 to 19. All attributes below 7 should be raised to 7 unless there is a very good reason not to. 7 to 8 should add two points and 9 should add one. A good cut-off point for high attributes of any kind should be 15 unless the character in question is really important (like a Birthright noble or office-holder).

Also try to think outside the box. Advantages like Combat Reflexes are certainly assumed to be part of a D&D attribute score. If you like use the exact point cost to convert part of the points of the adjusted attribute to advantages.

Re: Converting NPCs from AD&D to GURPS
 

Convert by concept, not mechanically. The assumptions on both systems are very very different.

if you're dead set into making a mechanical conversion, 3.X, I would convert using the attribute bonus, so Dex 12 would convert to DX 11. ST might be treated differently, and converted 1 to 1. Now, AD&D had strange bonus scales from attributes IIRC, meaning that this is even harder, specially when you consider Str 18/XX. Still, the rationale stands. For ST, use 10+damage bonus. For Dex, use AC bonus. For Con, use the bonus to disease/poison save as the HT bonus (not the HP bonus). For Int, I really don't remember the bonuses it game well enough. Same for Wis and Cha.

There's only one reason for mechanical conversion, and it's NPCs were you only have the class level and stats, with no background, and still, it's quite better to see what concept they embody before starting the conversion.

Re: Converting NPCs from AD&D to GURPS
 

This. One can come up with a comforting mechanism to convert primary attributes because they're more or less on the same scale, but I find that it's a bit of an illusion, since GURPS stats have more profound implications than D&D ones. Moreover, things start to get whacky when you move into conversion of levels, feats, proficiencies, and D&D-flavored skills into advantages and GURPS-flavored skills, where there's little or nothing in the way of correspondence. You're going to have to do most of it by concept anyway, so you may as well do the whole thing that way.

Re: Converting NPCs from AD&D to GURPS
 

In terms of sheer probabilities, each +1 to a D&D stat is +5% to success chances. That isn't true with GURPS, which uses a bell curve. Going by probabilities, I would get this, roughly:

GURPS D&D
5 1
6 2
7 4
8 6
9 8
10 10
11 13
12 15
13 17
14 18
15 19
16 20

Bill Stoddard

Re: Converting NPCs from AD&D to GURPS
 

I always got reasonable results converting strength based on lifting capacity. For large monsters, I use the guidelines from the Growth Advantage to determine a minimum ST based on size and then tweak from there. Most large monsters become unbelievably deadly. Hehe.

Levels should translate into higher skill levels, in my opinion. Pick a few core skills, based on class, and increase them accordingly. Or, add a number of character points for each level and allocate them to those core skills.

Sometimes a hybrid method that mixes the mechanical approach and the concept approach is nice. This is what I usually do.

Pick a few reasonable rules of thumb for basic stuff and add flavor as you convert. Customize and make the character better than it was in AD&D. Make it your own.

Re: Converting NPCs from AD&D to GURPS
 

Funny, I was coming up with something for this. The pre-3e editions of the game were sparse for stats for NPCs; for 3e and later, you convert the bonus. I assigned stats from a table for older NPCs, which were keyed to be below a DF character at 1st level.

The basic idea, in the end, is that every class is a bang skill, specifically one in Dungeon Fantasy. Weapons other than those listed in the DF bang skill go up as another skill, and the classes get a few common advantages and disadvantages (all barbarians get Great Rage from DF11 since that handles their 3e Rage ability; clerics get True Faith (Turning); monks get Catfall; you get the idea). The idea is to be able to convert an older module (I was looking at Temple of Elemental Evil) almost on the fly, though I don't think I've done that.

If you want to convert every little feat and skill, that's your headache. I'm going more for a 12th level Monk knows Martial Artist! at DX+3 and you handwave most of the details as, "Yeah, he should be able to do that."

Re: Converting NPCs from AD&D to GURPS
 

I have always converted at a 2:1 ratio, i.e.,

11-12 = +1 in GURPS
13-14 = +2
15-16 = +3
17-18 = +4
18 + % (for ST) = 15

Re: Converting NPCs from AD&D to GURPS
 

I'm currently playing with converting ADnD Dark Sun into GURPS 4th. And my take on it is to go for the feel not the hard conversion. I just ran into far bigger problems then I wanted to deal with to convert ADnD to GURPS directly. The main one being how much damage can a character handle. GURPS is at its base a deadly system and ADnD is not. Both can be converted to the other, but I feel it's easier just to go for the feel of things rather then do that conversion.

Re: Converting NPCs from AD&D to GURPS
 

A lot depends on how you plan on setting up your world and what points scale you want to use.

Think of the best warrior in your setting. Do you see this guy as a 300 point character? 500 points? 1000 points?

This will determine a lot about how you should convert over the D&D characters.

For me when I've done it in the past I shot for 10th level characters being about 300 points and 20th level characters being about 500.

I think an easy conversion is to just look at their Modifier for their D&D Stat. 11 for a +1, 13 for a +3 and 15 for a +5 sounds about right to me. At least for DX and IQ. You might be able to convert ST and HT straight over.

Still, you are going to get way better results by just doing it by points. Toughness, High Pain Threshold, etc are going to go a lot farther than +1 or +2 HT.

And keep in mind that converting some things over will just end up being a lot of points. Shardminds for example are immortal and can speak to any intelligent creature. That's a freebie in D&D, but not in GURPS.

Re: Converting NPCs from AD&D to GURPS
 

Strength Conversion
Based on comparing AD&D 2nd Ed Max Press to GURPS 4th Ed Heavy Encumbrance

Direct:
AD&D 2nd Ed___GURPS 4th Ed
Strength________ST
1______________1 [-90]
2______________2 [-80]
3______________3 [-70]
4-5_____________5 [-50]
6-7_____________7 [-30]
8-9_____________9 [-10]
10-11___________10 [0]
12-13___________11 [10]
14-15___________12 [20]
16______________13 [30]
17______________14 [40]
18______________15 [50]
18/01-50________15 or 16 [50 or 60]
18/51-75________16 [60]
18/76-90________17 [70]
18/91-99________18 [80]
18/00___________20 [100]
19______________23 [130]
20______________24 [140]
21______________26 [160]
22______________28 [180]
23______________31 [210]
24______________35 [250]
25______________38 [280]

Smoothed out at the lower levels:
AD&D 2nd Ed___GURPS 4th Ed
Strength________ST
1______________1 [-90]
2______________2 [-80]
3______________3 [-70]
4______________4 [-60]
5______________5 [-50]
6______________6 [-40]
7______________7 [-30]
8______________8 [-20]
9______________9 [-10]


Smoothed out exceptional Strength:
AD&D 2nd Ed___GURPS 4th Ed
Strength________ST
18/01-50________16 [60]
18/51-75________17 [70]
18/76-90________18 [80]
18/91-99________19 [90]
18/00___________20 [100]

Smoother but less accurate table:
AD&D 2nd Ed___GURPS 4th Ed
Strength________ST
1______________1 [-90]
2______________2 [-80]
3______________3 [-70]
4______________4 [-60]
5______________5 [-50]
6______________6 [-40]
7______________7 [-30]
8______________8 [-20]
9______________9 [-10]
10-11___________10 [0]
12-13___________11 [10]
14-15___________12 [20]
16______________13 [30]
17______________14 [40]
18______________15 [50]
18/01-50________16 [60]
18/51-75________17 [70]
18/76-90________18 [80]
18/91-99________19 [90]
18/00___________20 [100]
19______________23 [130]
20______________24 [140]
21______________26 [160]
22______________28 [180]
23______________31 [210]
24______________35 [250]
25______________38 [280]

Re: Converting NPCs from AD&D to GURPS
 

Other Attributes

AD&D 2nd Ed___GURPS 4th Ed
Attribute_______ Attribute
1______________-90 points in Attributes/Disadvantages
2______________-80 points in Attributes/Disadvantages
3______________-70 points in Attributes/Disadvantages
4______________-60 points in Attributes/Disadvantages
5______________-50 points in Attributes/Disadvantages
6______________-40 points in Attributes/Disadvantages
7______________-30 points in Attributes/Disadvantages
8______________-20 points in Attributes/Disadvantages
9______________-10 points in Attributes/Disadvantages
10______________No modifiers
11______________10 points in Attributes/Advantages
12______________20 points in Attributes/Advantages
13______________30 points in Attributes/Advantages
14______________40 points in Attributes/Advantages
15______________50 points in Attributes/Advantages
16______________60 points in Attributes/Advantages
17______________80 points in Attributes/Advantages
18______________100 points in Attributes/Advantages
19______________120 points in Attributes/Advantages
20______________140 points in Attributes/Advantages
21______________160 points in Attributes/Advantages
22______________190 points in Attributes/Advantages
23______________220 points in Attributes/Advantages
24______________250 points in Attributes/Advantages
25______________280 points in Attributes/Advantages


Notes:
All Attributes Start at 10
IQ! = IQ – (PER+WILL)

Dexterity
Advantages: Basic Speed [5/Level]; Enhanced Defences [Variable]; DX [20/Level]; Flexibility [5 or 15].

Dexterity 19: Cat Fall [10] and Perfect Balance [15] are available.

Disadvantages: Combat Paralysis [-15]; Klutz [-5 or -15]; Reduced Basic Speed [-5/Level]; Reduced DX [-20/Level].

Constitution
Advantages: Extra FP [3/Level]; Extra HP [2/Level]; Fit [5 or 15]; Hard to Kill [2/Level]; Hard to Subdue [2/Level]; High Pain Threshold [10]; HT [10/level]; Less Sleep [2/Level]; Longevity [2]; Rapid Healing [5 or 15]; Resistant [Variable]; Resistant to Eternal Rest +3 or +8 [1 or 3].

Constitution 18: Immunity to Eternal Rest [5] is available.
Constitution 19: Recovery [10] and Regeneration: Slow [10] are available.*
Constitution 20: Regeneration: Regular [25] is available.
Constitution 25: Regeneration: 1HP/10minutes [35]** is available.

*I added Regeneration: Slow to smooth the progression from no Regeneration to Regeneration: Regular
**GURPS Hellboy

Disadvantages: Easy to Kill [2/Level]; Low Pain Threshold [-10]; Reduced FP [-3/Level]; Reduced HP [-2/Level]; Reduced HT [-10/level]; Unfit [5 or 15].

Intelligence
Advantages: Eidetic Memory [5 or 10]; IQ! [10/Level]; Language Talent [10]; Languages [1-6] ; Lightning Calculator [2 or 5]; Non-Combat skills [Variable]; Versatile [5].

Intelligence 19: Immunity to Illusions [15] is available.

Disadvantages: Absent-Mindedness [-15]; Bestial [-10 or -15]; Confused [-10]; Hidebound [-5]; Reduced IQ! [-10/Level].

Wisdom
Advantages: Common Sense [10]; Empathy [15]; Fearlessness [2/level]; Indomitable [15]; Intuition [15]; Perception [5/level]; Unfazable [15]; Will [5/level].
Disadvantage: Cowardice [-10*]; Fearfulness [-2/level]; Gullibility [10*]; Impulsiveness [-10*]; Overconfidence [-10*]; Reduced Perception [-5/level]; Reduced Will [-5/level].

Charisma
Advantages: Appearance [Variable]; Charisma [5/level]; Fashon Sense [5]; Smooth Operator [15/level]; Voice [10].
Disadvantages: Appearance [Variable]; Clueless [-10]; Disturbing Voice [-10]; No Sense of Humor [-10]; Odious Personal Habit [Variable].

Re: Converting NPCs from AD&D to GURPS
 

Did you already take a look at that project? Could be helpful, though it's 3e... www.skripczynski.de/projects/dark-sun/
And even more so, this thread for 4e: http://forums.sjgames.com/showthread.php?t=77123

Re: Converting NPCs from AD&D to GURPS
 

Yes. This is one reason why concepts translate better than stats. Also, you need to ask why you want game stats at all. In most games, it means the players are going to kill the NPC, or at least be in some sort of combat with him, whether as friend or foe.

Attributes relative to the PCs is another way of handling it. In a DF game – the presumed output for D&D characters – the templates average about 12 for the basic attributes, a bit more for DX. Since the templates represent adventurers with a few levels already, your mooks should be lower.

Re: Converting NPCs from AD&D to GURPS
 

I want to be able to stat out a number of important NPCs to assess how valuable a patron they can be. Also as stated above, I tend to do more work than necessary. However, no one wants to GM a scene where Prince Avan is there to do important social stuff with a few brief notes, when it turns out the party wants to murder him for his blood (perhaps because of the important social stuff).

Re: Converting NPCs from AD&D to GURPS
 

Well, it matters a lot for social interaction by the rules what the NPC's IQ and Will is. Per can matter in a lot of cases where there's no combat, either. And skill levels can come up during all sorts of interaction.

Re: Converting NPCs from AD&D to GURPS
 

A work in progress:

I'll explain my notes, which I mostly copied and pasted from the Notes app.

The "Class" column represents going up in the bang skill for that class; all go up 1 relative skill level every 4 levels. "Weapon" represents going up in skill for weapons not on the bang skill; "Stat" means whatever stat gets boosted. "Other" means anything else that might go up with level; "ER" is an Energy Reserve. The second table is mostly a listing of traits that a generic member of that class would have, which is mostly Advantages and Disadvantages that always show up on the template, with some common abilities for those templates dependent on Powers.

The armor table at top is a list of cheap armor that would be common to NPCs.

Re: Converting NPCs from AD&D to GURPS
 

That's a definite case where going with concept is better than game stats, since Patrons seldom see combat.

The stats are all 10 unless you know otherwise. The skill level should use the GURPS guidelines: 5 or so for default, 8-9 for background skills, 10-11 for secondary skills, 12-13 for professional level, and 14-16 for a good professional; ramp up accordingly for good stats. You could use ranks in a skill as points in a skill for a really important NPC.

Re: Converting NPCs from AD&D to GURPS
 

Here is my first NPC. I decided to mostly build him from concept, but I took a few of NineDaysDead's ideas for tweaking scores to my liking.

I started with a 9th level fighter trained in a Brecht (read German/Hanseatic/Venetian) fencing school. He is a ruthless political mastermind, acts as head of his own police force as well as those of many of his neighbors, rules the richest and most powerful state in Anuire, and possesses perhaps the most legitimate claim on the title of Emperor.

I started with a Swashbuckler Template, added in a Swashbuckler-Knight Mixed Profession Lens, improved his IQ to match his AD&D stats (via NineDaysDead's suggestions), gave him every Social Advantage that seemed proper, before finally adding a handful of skills that seem important to a Prince who must administer a state.

I have not attempted to show any of his mortal allies, contacts, or dependents, nor have I included a representation of his bloodline score or strength (mystical empowerment from dead gods found in all rulers in this setting). However I have included his blood abilities (special powers gained via his bloodline).

Let me know what you think.

Darien Avan
750 points
Late 40s; Light skin, brown (greying) hair, brown eyes, purple birthmark in the shape of a dragon on left side of face;

Attributes: ST 12 [20], DX 15 [100], IQ 14 [80], HT 13 [30],

Secondary Characteristics: Dmg 1d/2d-1, BL 29, HP 12,

Will 12, Per 12, FP 13, Basic Speed 8, Basic Move 8,
Dodge 11, Parry 21 (Main-Gauche), 18 (otherwise).

Wears enchanted elven chain (DR 6).

Advantages: Ally (Air Elemental; Built on 100%; constantly available; PM, -10%; Summonable, +100%) [38]; Ambidexterity [5]; Animal Empathy (Lions only, -80%; PM -10%) [1];Born War Leader 2 [10]; Charisma 2 [10]; Combat Reflexes [15]; Enhanced Parry 3 (Main-Gauche) [15]; Extra Attack 1 [25]; Feudal Rank 6 (Prince of Avanil) [30]; Handsome [12]; High Pain Threshold [10]; Independent Income 20 [20]; Legal Enforcement Powers [15]; Legal Immunity [15]; Luck [15]; Multimillionaire 2 [100]; Police Rank 6 [30]; Regeneration (Regular; PM -10%) [23]; Reputation 2 (Future Emperor; Allies and Subjects, -50%; All the time) [5]; Social Regard 2 (Respected; PM -10%) [9]; Speak with Animals (Lions only, -80%, PM -10%) [5]; Status 6 [0]; Striking ST 1 [5]; Weapon Bond (Scalebiter) [1]; Weapon Bond (Heartseeker) [1]; Weapon Master (Rapier and Main-Gauche) [25].

Disadvantages: Delusion ("I am the best man since Emperor Roele") [-5]; Obsession (Become Emperor of Anuire) 9 or less [-15].

Skills: Acrobatics (H) DX [4]-15; Administration (A) IQ+1 [4]-15; Area Knowledge (Anuire) (E) IQ [1]-14; Area Knowledge (Avanil) (E) IQ [1]-14; Armoury (Melee Weapons (A) IQ [2]-14; Brawling (E) DX+1 [2]-16; Carousing (E) HT [1]-13; Climbing (A) DX-1 [1]-14; Connoisseur (Literature) (A) IQ-1 [1]-13; Current Affairs (Headline) (E) IQ [1]-14; Current Affairs (Regional, Avinil) (E) IQ [1]-14; Dancing (A) DX-1 [1]-14; Detect Lies (H) Per-1 [2]-11; Diplomacy (H) IQ+3 [8]-17*;Fast-Draw (Knife) (E) DX+1 [1]-16†;.Fast-Draw (Sword) (E) DX+1 [1]-16†; Fast-Talk (A) IQ [1]-15*; Finance (H) IQ-1 [2]-13; First Aid (E) IQ [1]; Games (Tournament Rules) (E) IQ [1]-14; Heraldry (A) IQ [2]-14; Hiking (A) HT-1 [1]-12; History (Anuirean) (H) IQ-2 [1]-12; Intimidation (A) Will-1 [1]-11; Jumping (E) DX [1]-15; Law (Anuirean (Avanese)) (A) IQ [2]-14; Leadership (A) IQ+4 [2]-18*‡; Main-Gauche (A) DX+4 [12]-19§; Military Science (H) IQ-2 [1]-12; Politics (A) IQ+1 [4]-15; Public Speaking (A) IQ+3 [4]-17‡; Rapier (A) DX+4 [12]-19§; Savoir-Faire (High Society) (E) IQ+1 [2]-15; Sex Appeal (A) HT+1 [1]-14*; Stealth (A) DX-1 [1]-14; Strategy (H) IQ+1 [2]-15‡; Tactics (H) IQ+1 [2]-15‡; Wrestling (A) DX [2]-15; Persuade (H) Will [4]-12; Riding (A) DX-1 [1]-14.

Languages: Anuriean-Native (default) [0]; Brecht-Accented [4].

Darien Avan, Prince of Avanil, runs not only his own kingdom, but significant portions of other provinces as well. Though he inherited much from his father, Veladan Avan, he has managed to amass an even greater portion of wealth and power than any had dreamed possible. It did help that partial stewardship of the City of Anuire itself passed to him with the death of his father. Nonetheless, Darien Avan capitalizes on any opportunity to expand his domain.

This middle-aged prince seems well versed in the uses and abuses of power. He strives for law and moderation in all things, but he, like the Archduke of Boeruine, appears willing to sacrifice his compatriots to gain the Iron Throne. He believes that his knowledge of power will serve him well, and that he could be the best thing to happen to Anuire since Roele himself. None dare to gainsay him.

* Includes +2 for Charisma
† Includes +1 for Combat Reflexes
‡ Includes +2 for Born War Leader
§ Includes +1 for Weapon Bond

Re: Converting NPCs from AD&D to GURPS
 

I think he works really well as a high fantasy character in GURPS. I would have put more points in some skills, but the high stats do more or less the same.

I don't think he can do everything a DnD character can do, but that's more about system then this characters writeup. Fore example in DnD he could easily charge 20 goblins with bows. In GURPS the same group would turn him into a pincushion (Well except for the air elemental, but not all fighters have one). Also a good mage with a high instakill spell will take him out.

But having said that I think you have gotten about as close as you can to a High power DnD character in GURPS.

SIDE QUESTION:
At what level does a DnD character conversion in GURPS get combat reflexes. What about Weapon Master? Is it different between classes?

Yes I had, but thanks. Half the fun is in the doing.

Re: Converting NPCs from AD&D to GURPS
 

Interesting...as the previous poster mentioned he will have...difficulty with mages.

I would not worry so much about instakill spells (HT resists) as mindmucking spells (IQ/Will Resisted).

The 150 pt/50 dis mage that I built for the most recent run I was in (low fantasy) would not have a ton of difficulty working around this gentleman...and he only had 3 Mental spells but Foolishness and Daze can get a lot of yardage handled properly. Invisibility and some of the others would also be...useful.

A true "Psi Cop" with Mental Control spells up to Enslave would be a potential grave difficulty for the prince.

If I were building him I would do it a little different (for that type of "hard charger" I do not think I would buy down Will for one instance.); if handed it to play as a pregen the first things I would do (in a High Fantasy setting) would be A- buy some enchanted items based around Magic Resistance spell etc. B- hiring at least one (better a number of unaquainted) mages to work in my employ long term to have coverage in those areas.

As to the PCs deciding to kill the prince..my first thought is how?

If it is a social event...they will not be armed and armoured...at best they will be in their best doublet and hose...with a rapier or similiar "social" weapon.

They will not be alone with the prince...most of the court will be there in similar social gear. Many "may" be useless social butterflies, many may be otherwise.

Some will be loyal and will fight to defend, some may not be loyal, but will see advantage in being publically seen as being so and thus may fight also.

Then there would be the princes guards...this isnt a social occasion to them...this is another day on the job...sure they just stand around vaguely like statues almost blending into the furniture...until something like this happens. And they will be fully caprisioned in the best tactical gear that money can buy!!

Killing the Prince would be nigh impossible (IMHO), surviving the attempt doubly so...

These are a couple of my early thoughts...

Good Luck and enjoy!!!

Re: Converting NPCs from AD&D to GURPS
 

I like your conversions. But are you sure that Max Press is conceptually the same as Heavy Enc?

I would have thought it'd be 8xBL, as per p. B15, "Quadrupling the time, and using two hands, you can lift 8xBL overhead". Max Press as presented in AD&D doesn't seem like it's meant to represent a weight you're going to be expected to lug around with you, but rather how much you can lift at maximum strain. It's the statistic that corresponds to the real-life max amount of weight that professional weightlifters can lift (I recall there even being a statistic cited comparing the then record holder's max lift with an 18/00 guy's Max Press), but that value by no means would correspond to what they could realistically sustain lifting like that.

As a total aside, is anyone aware of any good conversion between original D&D (pre-1st ed) ability scores and either GURPS attributes or even AD&D 2nd ed ability scores? Because I wanted to convert some really old things out of the D&D Immortals set and my gut is that those ability scores are not 1:1 with either GURPS or less obviously with AD&D 2nd ed.

Re: Converting NPCs from AD&D to GURPS
 

My conversion gives Strength 10-11 as equalling ST 10, and Strength 18/00 as equalling ST 20. Your method would give something like:

AD&D 2nd Ed___GURPS 4th Ed
Strength________ST
10-11___________9 [-10]
12-13___________10 [0]
14-15___________10 [0]
16______________11 [10]
17______________12 [20]
18______________12 [20]
18/01-50________13 [30]
18/51-75________14 [40]
18/76-90________15 [50]
18/91-99________16 [60]
18/00___________18 [80]
19______________20 [100]

Re: Converting NPCs from AD&D to GURPS
 

What are the components of the bloodline power modifier?

Re: Converting NPCs from AD&D to GURPS
 

As is often my failure, I didn't contemplate the way that magic would uniquely intersect with this issue. I am thinking that I should give him (and all people with great bloodlines) Magic Resistance 3 (Switchable +10%). I don't know how I should handle blooded mages at the moment. But it seems out of genre for these great scions to be simply commanded by a mage. I will have to think on the subject.

I don't have a copy of Powers so I had to guess, perhaps you can help me establish it.

When the gods of this world fought and died their energies were sent out, those closest to them (literally and figuratively) were raised up to be new gods, those slightly further off gained True bloodlines such as Roele the soon to be emperor (and brother of new god Haelyn) and the Gorgon. Further down the ladder are those with Great, then Major, then Minor, then last were the people barely at the battle, or with only minor spiritual/moral connections to the gods; these people have Tainted bloodlines.

The principal benefit of having a bloodline is that it allows you to have a mystical connection to the land (or its institutions), effectively limiting the ruling class to people with a bloodline. It also acts as an unusual background allowing people to have blood abilities

Furthermore, blooded scions gain regency from wise or affective rule. This they can spend (in small amounts) to improve the chances of success for most large scale actions to run their domain. Or they can spend very large amounts of it to fractionally strengthen their bloodline.

Regents (scions who rule) effectively have a pact limitation forcing them to protect their domain and to maintain their alignment. Ignoring either will reduce both their regency and diminish their bloodline.

Everyone knows that anyone who strikes down a scion by stabbing him/her in the heart gains a measure of their power. Anyone from some random peasant to your own brother may attempt to kill you in this fashion. The principal antagonist NPC has hunted for and claimed the flower of Anuriean nobility once every generation for the last several centuries. There exists a dozen or so weapons which are remarkably efficient at this bloodtheft.

Lastly a scion may pass on the full strength of their bloodline to an heir, possibly at sword point, but not under magical compulsion. Once passed on the scion loses all benefits of their bloodline.

Re: Converting NPCs from AD&D to GURPS
 

It's easiest to give a straight Str = ST for D&D 3e/4e, and more or less correct too. For earlier editions, you might go with Str/2+5 = ST, with a bonus for exceptional strength. Lifting ability is not important to D&D, so don't fret about it too much.