@Roadie Since you seem to be an expert on GURPS, if the QMs DID decide to go with it, would you be available for reference? For both us and them
Yes, but irregularly.
Better general advice would probably come from the GURPS forums, any, which have had occasional discussions on converting all kinds of things, including things much harder to model than Naruto, like Exalted.
In general, though, most of the stuff beyond the specifics of power representations is self-explanatory once you look through the books. In particular, stats, skills, and techniques make up the vast majority of what would be in use most of the time, plus a smattering of extended rules from different books.
The main extended-rules stuff I'd recommend to look at would be:
- Deceptive Attack (Basic Set: Campaigns p. 359) and Extreme Scores in Regular Contests (Basic Set: Campaigns p. 349), to handle resolving things sanely when opponents have very high skill ratings.
- Flying Combat (Basic Set: Campaigns p. 398), for use with skywalker seals.
- Hit Locations (Basic Set: Campaigns p. 398), for attacking specific parts of the body or striking at weapons or held objects, and commensurate effects.
- Energy Reserves (GURPS Powers, p. 119), if the GMs like the idea of representing chakra stores as a separate mechanical element from normal physical fatigue.
- Abilities Enhancing Skills (GURPS Powers, p. 162), for general guidelines on using special abilities to enhance skill rolls.
- Defending with Powers (GURPS Powers, p. 167) and Resisting with Abilities (GURPS Powers, p. 169), for general guidelines and options on using relevant powers alongside normal defenses (like using movement or transformation powers in place of Dodge/Parry).
- Super-Effort (GURPS Powers, p. 58) and Strength and Super-Strength (GURPS Supers, p. 24), for ways to model dramatic strength that doesn't add to striking damage at the same rate.
- The sections in GURPS Powers and GURPS Supers that add more modifiers to Advantages and Disadvantages, to aid in representing powers.
- Styles (GURPS Martial Arts p. 141), for assorted real-world fighting styles and Skills, Techniques, and Perks that go well with them, as well as rules for recognizing the styles used by others.
- Basically all of GURPS Low-Tech, for assorted equipment and weapon lists.
Honestly, I'd rather there be a scaling dice pool in accordance with skill than a set dice pool, but very few professional systems do that because of the difficulty in actually counting the dice: either that, or they only consider given numbers to be successes on a per-die basis, which comes with its own issues.
Shadowrun comes closest to my preference for dice mechanics, though it doesn't use numbers additively as I'd prefer; it just uses the success count method I mention above.
Just about every tabletop system with a die pool uses success counting. The only real exceptions I can think of are Risus (which caps out at something like 5 dice maximum at a time) and Exalted 3e (which is only kinda-sorta an exception, because it uses success counting but the actual numbers on the dice are also relevant for some effects).
