Question: Using D20 Stats with GURPS Character Creation

[Dalillama]

Originally Posted by Elliander

I am starting a new campaign where, for the setting I designed, we have decided to use GURPS as the base for overall Character creation, but we are going to be needing to use the base stats that are used in D&D. We are also going to be using a Spell Point system, a D20 Magic system, and we are going to be using a Shadowrun Movement point system.

With the exception of NPCs that I will be creating, the vast majority of monsters will be using Pathfinder stats which is why, for simplicity, I will want all of the players to have comparable stats.

So here's my basic question: How do D20 stats convert to Gurps stats in regards to character creation?

Poorly. It's not clear to me why you're not using the Pathfinder character generation system, as GURPS character sheets are likely to be quite difficult to accurately convert over to compatibility with Pathfinder rules.

From what I can tell, in Gurps, players choose their stats instead of roll them. Is there even a point at which characters "level up"?

No. GURPS is a point-buy system, which means that initial stats, skills, etc. are purchased from an initial pool of points. When more points are handed out (experience points), they can be spent to improve existing abilities or buy new ones, within the limits of the setting (e.g. in a D&D type setting, you probably can't spend your points on Pilot: X-wing fighter).

(and in that regards, how would I use a D20 spell system without having levels as a base line, unless players also choose caster level with points as well?)

I suppose you could change the prerequisite system, divide the GURPS spell list into 'spell levels' instead, and rule that you need X number of spells from the previous level before you can buy spells of the next level up. In most GURPS magic systems, spells are treated like skills, or based on skills, although you can build them as sets of advantages too (this takes a lot of work).

If I convert the stat function and use GURPS stat costs, what is the base line for figuring out what level the characters are to select an appropriate D20 opponent?

Popular figures from previous discussion tend to go round 100-200 points for first level, +25-50 points per additional level, but Pathfinder style Challenge Ratings don't really convert.

From what I can tell:

ST = Strength
DX = Dexterity
IQ = Intelligence
HT = Constitution
WILL = Wisdom
Per = Perception = a D&D Skill
FP = Fatigue = Non-existent in D&D

And Charisma appears to be non-existent in Gurps?

I'd convert slightly differently to Kalzazz, which just points up the difficulties involved.
ST= A mixture of Str and Con; ST determines lift, damage, and hitpoints
DX= A mixture of Str and Dex: DX affects your Dodge and your ability to learn and use weapon skills, and your speed.
IQ= Int, pretty much straight across. Affects your ability to learn and use spells and mental skills. No bonus languages, buy languages as usual.
HT= part of Con+ some other things. HT governs endurance, ability to resist poisons, drugs and environmental extremes, and also to survive extreme injury. HT also affects your Basic Speed and hence Dodge.
Will= A part of Wis; governs ability to resist interrogation, mental attacks, etc. Also the basis of some related skills.
Per= part of Wis; the governing attribute of skills that take the place of the Pathfinder skill Perception, and what you roll against to notice things when you haven't got a relevant skill
Charisma is an advantage in GURPS rather than an attribute. Purchasing it improves NPC reactions, but doesn't come with any of the other associated traits from Pathfinder (followers, bardic magic, etc.)
FP: Pathfinder doesn't really track this, although it would be equivalent to Magic Points if you're using the default GURPS Magic system.