I would love a time-travel game. There’s lots of ways you can do it of course, from the serious to the highly-camp and there’s plenty inspiration out there for a time travel game.
From Terminator to Quantum Leap. From Dr Who to the Time Machine. From Back to the Future to 12 Monkeys. Looper to The Time Traveller’s Wife to The Butterfly Effect. And lots more of course. Hey even Star Trek goes back in time.
First decide on what sort of feel you’re going for, if you want mad hijinks, lots of crazy fun adventure, or if you want a game that makes people think. Are you going to have a modern character travelling to the past. Or someone from the future travelling to modern day. Will they be travelling in their own lifetime, to change personal things or will they be travelling to huge historical events to make sweeping changes in the past.
I would think that sort of game would be best just written as a story, as any other game, not messing about with fancy commands to do it for you.
Although I suppose you could do fancy commands.
If I were doing it code-wise I’d probably do it Groundhog Day style. I recently read a book, the name of which escapes me, which was a teen version of Groundhog Day. Where a girl keeps repeating the same events over and over again and she has to work out why, uncover the mystery and which events she has to stop and which she has to let happen to break the cycle. I think that book would translate into a very interesting Choice game.
In it the girl has a number of choices. Whether she steals a student’s parking space thus causing them to be kicked off the swim-team, or she parks further away and gets detention herself. Who she sends Valentine’s Roses to. Whether she chooses her jock boyfriend, a nice boy, or gives in to a teacher’s advances. Whether she attends a party or not. Whether or not she engages in some bullying. And how can she stop the suicide of the girl that she and her friends have been bullying.
It’s very much a book with some very set scenes which repeat over and over again. As she learns more things about the different scenes more options open up.
Reading that book I couldn’t help but think it was very much a scenario that would work well for a Choose Your Own Adventure style game. Although I found the protagonist so utterly abhorrent as a person. I think she was meant to grow and change as the book progressed but she didn’t seem to really.
I think if doing that sort of very limited time-travel it could be possible to keep track of previous choices, of what your character knows, and let them loop over the game until they get the ending where they make the right choices.