Travel Between Game Worlds

One of the chief purposes of the GURPS design is to
let players explore multiple game worlds without learn-
ing a whole new set of rules each time. A player can
participate in several different campaigns, each in a
different place or time, and play a different character in
each campaign. Each character stays in his own world.
But the characters can also move from one game world
to another. This can happen in three ways:
1. A player can develop a character in one game
world and then bring that character into another game
world. An example might be a medieval wizard, hurled
hundreds of years into the future by a magic spell, par-
ticipating in a WWII adventure.
2. An entire campaign can move from one game
world to another. For example, suppose the party is the
crew of an interstellar trading ship. They crash-land on
a primitive planet. Until they can make their way to the
spaceport, on the other side of the world, they are effec-
tively living in the 12th century!
3. The campaign can include multiple game worlds
by design, along with the means to travel between
them. See Other Planes of Existence.