[quote=“jcd, post:4, topic:12013”]A most devious idea would be to make the time-travel the event that triggers the cataclysm (also limit time travel to 1-10years to keep it plausible)
So, whenever you return, its practically day 1 of the cataclysm and you get to see the chaos that ensued.
This is still really hard to code of course, but not impossible.[/quote]
Or like this:
Upon starting the time machine, the game PROMPTS “Jump back how many years? (1-12)”, and no matter what number the player enters, the result is always the same - a world reset. But it’s not going to stop anyone from being curious about what happens if he enters a different number. Muhahaha. … 
Additionally, the new (post-jump) game now includes a live copy of the player character, somewhere. Any damage or status alteration that this doppelganger sustains is inflicted upon the current player as well, potentially forcing the player to protect that guy at all times (pun not intended). If we really want to make this awesome, the game should record everything that the player does. This is so that in the new world the game can make the doppelganger repeat everything that the player did in the old world, and so that the new player character can track down the old player character, for whatever reason, or to stay the hell away from him, way outside the reality bubble.
Oh, and do you see? If you treat your present self well, your future self will be better off, and if you hurt yourself, you’ll be just hurting your future self! See? See?! I’m not crazy!
Also, for each year that the player chooses to jump, a single wild monkey is added to the game somewhere.