I had a couple ideas for game in the last couple of days. Like usual, they are both just rough ideas. So here they are.
A game where the players are trying to kill one another... but here's the twist. If you are killed, the game does not end; you can continue to play as a ghost. I think there would need to be an advantage to staying alive... you don't want all the players try to be killed... but the advantage needs to be not so big as to make it impossible to win as a ghost. Honestly, the thing I like about this idea is not the killing in and of itself, it's the idea that there could be a huge fundamental change to game imposed on you by another player, and you have to react to change. And the change needs to be final and unwelcomed, but not dooming to you as a player in the game. I've even thought that maybe it becomes more advantageous to be a ghost as more players die.
I used to play a computer game when I was young that I loved. It was called Defenders of the Realm. Essentially it was a Kingdom management game. You played a King the was trying to take over England and manage the counties in Kingdom at the same time. Right now you might be thinking "I've seen that 1000 times before." But here's the twist (I'm stealing this twist from Of Power & Glory): You are not the King.... and here's the other twist (I guess I'm all about twists today!) It's a co-op game. You and your fellow players are Nobles that are responsible for managing the various concerns of the Kingdom. Every co-op game needs a enemy or two. In pandemic, it's the viruses, in Flash Point it's the fire.... here, it's your boss. And maybe the Kingdom(s) in the area too. I think there's a lot of opportunity for "stress" with the needs of the Kingdom, and the King and the threats of your enemies all stretching you in different directions.