Some principles for creating an expansion, from Scott Caputo (designer of Kachina/Völuspá):

  1. It has to be desirable.
  2. It has to feel like part of the original game.
  3. It cannot make the game feel overly long.
  4. The new [components] have to work well together.
  5. It needs to allow for more planning.


Lessons learned designing an expansion, by Grant Rodiek (@HerrohGrant):