by cbs42
There are lots of different ways to do it, since it's a house rule.The way I like to play is by making it worth the total number of players that are still currently in the game, regardless of their location. I like to do this in combo with ignoring the Tokyo Bay optional rule, and just having the one Tokyo spot no matter how many players are in the game. That makes Tokyo a huge risk and a huge reward, and it smoothly scales down as players get eliminated.
It's also fun to play around with different starting levels of energy, to make for a little more action with the cards earlier in the game.
Play it however it's most fun for your group. Just make sure everyone is aware of the house rules before the game starts. One fun thing to try out is to play a bunch of times in a row, and allow the winner of the previous game decide the house rules for the next one.