Jürgen Hubert said:
That being said, I have my doubts if d20 can do Transhumanist SF well - at least without a lot of changes.
Why not, IYO?
I think any talk of genre w/r/t what d20 (or any system) can "do" is sort of tangential, because there's a lot to genre that's often really just color, in RPG terms. E.g., I'm prepping the original
Gamma World module
Legion of Gold for a Gameday event. The adventure is basically a dungeon crawl with some wilderness encounters; it even begins with, "You all meet up in a tavern," though it uses the term "saloon." But, it's post-apoc sci-fi, not high fantasy. Why? Because you fight mutants, not goblins. I'd point to Mearls comment above about the
Serenity dungeon-crawl, too.
Ergo, I think the bigger question is whether d20's framework will allow your game to do what you want it to do, not just whether it will fit the genre trappings. We know d20 is great for a game focused on tactics and resource-management, but what about a game focused on thematic play? Or "reality simulator" games like GURPS or HERO? (
d20 Modern and SC2.0 start getting into the latter territory a bit, IMO.)
I'm not sure I have an easy answer to this question, because it brings into discussion, "When is a game no longer d20?", i.e., how much modification can you make while still calling a game d20 (touched on by the Dancey quote upthread).
For me, a game is d20 if my existing knowledge of systems like D&D and d20M are still useful. So, M&M is d20 in my book, as despite the classless, level-less, power-based system, it still feels d20 mechanically to me. And, it's largely doing the tactics + resources thing.
But, if you took, say,
HeroQuest's roll-under d20 mechanic and made it roll-over, and then switched character traits to bonuses instead of target numbers, that'd basically be the core d20 mechanic... but I don't think that would be enough, as the rest of the system wouldn't build much on my existing d20 knowledge, and doesn't really focus on tactics (AFAIK; I could be wrong).
So, back to transhumanist SF... Having read the first
Transhuman Space book (which rawks, BTW), I don't really see anything about it that you couldn't do with a d20 framework. A lot of the SF material published for d20M already does it, in fact.