The basics of Special Relativity is quite simple. I think that a 7 year old kid could be made to understand it. But the General relativity... HOOOA! Here we are talking Greek!
Personally I don't like the WoD/Shadowrun style to determine successes. "Let's see now... you have to roll fifty-eleven D10. You fail unless you have XXX successess."
OK, it is very easy to understand the systems, but I don't think that it is very smooth when you have to roll some ten dice to determine how well a character succeeds with something.
Basically, what I mean is that I opt for the D20 as in Kult or in the same way as it is done in DnD, Spacemaster and some other games. You roll a DX and add your skillbonus. The higher the effect the better it is.
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