Knightfall
World of Kulan DM
Quantum tunneling sounds interesting, but I'm not too familiar with the concept. Is that right out of Sliders? (*) Or is it some sort of Real WorldTM theory?Knightfall, I just had an idea regarding doubles. Perhaps some earths have a slower rotation speed than others, thus making it seem like one is time-traveling when going to another Earth. The thing to keep in mind though is that 'Quantum Tunneling' between earths is never time travel.
One the earths that have a slower rotation speed, you can use to springboard doubles of figures that have long been dead on our Earth or just younger versions of NPCs and/or PCs.
With this idea, it might be possible to intervene in the double's character development by having the other, older double, intervene at key points in the youger double's life.
Regardless, time travel won't be a "major" part of AlterEarth. Character doubles in this campaign will be from otherworlds, so an NPC from Earth might have a duplicate on, say, Toril or Kulan. Now, that NPC might also have a duplicate on an alternate Earth, but my focus won't be on that idea unless the alternate Earth is radically different from AlterEarth.
(*) It's been a long time since I watched Sliders.