Empire Building
No problem!
1) Handling loss (attrition).
- One, my game features a lot of "Secrecy" (players are not totally aware of everything about each other at the outset). Thus, if a player "leaves" - I just blank out all of their information. Where they are "poofs", their "stuff" poofs, etc. However, if they left any mark on the game (such as destroying a city); that stays in effect.
- - short version: remove the footprint of the player, but, not necessarily the results. This way no one benefits from that player leaving, but, there's no sudden whiplash on the world itself.
2) Handling new additions.
- This largely depends upon how you feel about new players entering altogether.
- In some games, I've said "you start exactly as everyone else has started."
- Others I've provided some small startup bonus (so - the game I run uses "gold" and "actions" as key resources.) - I've gone ahead and provided an "X amount of gold" multiplied by the # of turns that have taken place. - They're in no way ahead of the existing players, but, typically aren't impossibly far behind either.