Time Travel: possible within a board game?

It seems to me that you have to place a limit on the amount of time travel you can perform. Ala Dr. Strange. Say the player can only go back in time within 4 rounds of play. Each turn and action adds one round, and your encounters get turned face up each round. The encounters could span 10s or hundreds of years and not necessarily be in sequential order. If you die you have to replay that round and the following round. If you cannot defeat that one round and it becomes unobtainable to return, you lose/ die.

Unlike Dr. strange, maybe the device has limited charges to permit going back in time to previous rounds. It costs more to go back 2 rounds than 1 round. Or possibly there is an item or event you have to perform in one round to live in the new round. It seems to me that each round should have a high likelihood of death to make it challenging enough for being able to live again.

For me it seems like messing with time could have disastrous consequences and your player is trying to restore order and live. They have to solve puzzles, fight antagonists, get items and live. The first time they use the device they have no idea where they go, but have managed to be able to lock in.

Another possibility is that the present day is known and the next five encounters are known. The player has to manipulate the tiles to reposition the time they are from at the end of the next five.

Really fun concept, I look forward to seeing it move on.

What would the function of the time travel be?

Undoing the choices that a player made?
Undoing the choices that an opponent made?
Resetting the game to a certain point, while keeping one or several items?

I read through your attachment, but didn't find enough to give much informed feedback on your particular design (aside from what I will mention at the end of this post), so instead I am going to talk about my observations about time travel in games and how I went about designing my own game, which will hopefully be helpful to you.

Time travel in board games is not unheard of; in fact, there are several games out there that are themed around time travel. However, there is a big difference between a game with a time travel theme and a game with time travel mechanics.

For example, consider Chrononauts, a classic Looney Labs game with similarities to Fluxx. In Chrononauts, time is represented as a timeline of event cards, and by changing one event card you can cause others to change later in the line. However, this is really just time travel as a theme - causality is just the arbitrary relationships that the designers decided certain cards to have, and there is no real feeling that you are changing your past or future within the game. Incidentally, while I find this game mediocre I love the theme - players are from different possible futures and are trying to alter the timeline to ensure that their future happens, erasing the futures of their opponents in the process.

Another example of a game with a time travel theme that doesn't quite reach the mechanics is Anachrony, a worker placement game in which you can send resources back in time - sounds exciting, but in fact it is just a thematic explanation for a loan. You gain a resource now and have to sacrifice a matching resource in the future or else bad stuff happens and you lose victory points - it works, but it still just feels like theme.

The only published board game I have played where the mechanics do really feel like time travel is Tragedy Looper, a game in which one player (the Mastermind) understands the goals and the causal relationships in the game and the rest go in completely ignorant. The Mastermind has a tragedy that he or she wants to cause, and the players are trying to figure out what it is and how to stop it. When they inevitably fail, they are sent back to the starting state of the game and play again, armed only with whatever information they learned the first time around. If they can prevent the tragedy even once (within a limited number of loops), they win.

The reason that Tragedy Looper feels more authentic, I think, is the way it focuses on the idea of changing the past, which is one of the major appeals of time travel fantasy - what would you do if you were given a second chance? It gives the players the opportunity to see how their past choices played out and challenges them to bring about the changes they want to see with their own actions, using their improved understanding of the causal relationships in the game that they gained through trial and error. Games that lack this aspect of changing the choices that you made earlier in the same game feel like the time travel is just thematic, not part of the game mechanics themselves.

Tragedy Looper has time travel, but all players travel back at the same time and play through the same timeline. For the next level of time travel mechanics, you need players to be able to play through different points in the timeline simultaneously - from what I understand about your game, this is the sort of time travel experience that you are trying to create, and it is also the most difficult.

The most authentic feeling time travel mechanic I have ever experienced is the way time travel works in the Achron, an RTS released in 2011. In Achron, in addition to the standard minimap there is also a timeline - it is possible for players to independently travel to different points in the game, up to about 8 minutes in the past or 2 minutes in the future, and play at different points in time simultaneously. This is accomplished through the concept of timewaves, which propagate changes made in the past to the future slowly, rather than instantaneously. If you go back in time and order your armies to destroy a factory, the ripple effects of its destruction propagate through time at a rate of 2 seconds per second (or faster if the player is actively observing them), giving your opponent in the present or future time to react before it disappears.

Sadly, Achron made some terrible design decisions for its gameplay (unrelated to the time travel mechanics), crippling an otherwise revolutionary genre. But the lesson to take away from it is that if you want players to be able to play simultaneously at different points in the timeline of the game, you need to make sure that changes to the game state in the past do not immediately propagate to all points in the future.

I was inspired by Achron to try my hand at a time travel board game allowing simultaneous play at different points in time. I came up with Paradox [1], the rulebook to which I have linked at the bottom of this post in case you are curious. The time travel mechanics of Paradox felt authentic to me, but much like Achron, the gameplay itself felt mediocre. The most important thing that I learned from the process, which I suggest you consider carefully if you want to make a game with a similar interpretation of time travel, is that time travel mechanics of this sort add crippling levels of upkeep. If you want a player's decisions in the past to matter, their effects need to ripple through the timeline to affect the future, but that means you have to compute the game state in each subsequent round. And as I (coincidentally) pointed out in a recent blog post, procedures like this are not free.

The system I came up with in Paradox involves ripple tokens, which indicate objects that may be affected by a time-traveler's actions. Each action that you can take has very specific rules about which objects receive ripple tokens as a result, and whenever you propagate changes to the next point in time, you only need to pay attention to objects with a ripple token to determine if they need to change. Anything without a ripple token could not have been affected by the time traveler's changes, and therefore can be ignored, which simplifies the necessary procedures. By adopting a turn-based variant of Achron's "time waves", procedures can be further simplified by only updating one round's worth of changes per turn (as opposed to the entire timeline).

Another possible approach that I considered (but never implemented in a game) is to have a real time game where you reward players for updating the timeline. Players would all be making changes simultaneously, spending some sort of action resource which they could regain by propagating changes from one turn to the next. The downside to this system is that it would be very chaotic.

One thing I did notice about your game is that it sounds like time travel is only usable by the time traveler faction, which means that you would need to build some very complicated machinery into your game to handle event propagation for the sake of just one faction. If you add that much weight to your game, it is probably worth giving the other factions a way to use time travel as well, unless it is the type of game where it is one player (the time traveler) versus everybody else.

[1] https://stonearchgames.com/wp-content/uploads/2019/12/Paradox-3.pdf

Talking about "simple" ideas... There exists in games such a Civilization a research timeline with various centuries and discoveries interconnected as a player travels through time (as normally).

In this sort of "technology tree", it could be possible to RE-ARRANGE the past and affect the tree in the future. Similarly it might be possible to re-arrange the Future with insights into some point in time with an advancement that has yet to be discovered occurring way ahead of the science that allows it to exist.

For example, what if the Egyptians discovered "Gunpowder"! How the tech tree would be altered with such a discovery. And that could affect the future tech tree also. I think the idea is to go "into the future" and then travel "back to the past" to bring things of VALUE... That could alter the timeline and progression of factions in different time periods.

I'm not sure how FEASIBLE the idea is... Never the less, it's in relation to the discussion about "Time Travelling": you've got to want to do it for SOME REASON!

I know this is an older thread, but I got to play Time Chase over the weekend. It is a trick tacking game that gives players the ability to travel back in time to take past tricks. It cost resources to do so and if you travel into the past you cannot be in the present to try to win the current trick. I thought that it is a fairly good implementation for time travel.

Sorry in advance for the long post. I didn't have time to write a short one.

Just took a gander at this thread for the first time, and I've got to say I'm impressed by some of the directions you've explored. From my understanding, this is a challenge a lot of designers have tried to tackle, and as you've seen, very few have been successful.

If you're still interested in exploring this faction, my suggestion would be to leave behind the literal traveling into other rounds, but use thematic mechanics as Quest alluded to above. Here are a few ideas you could maybe consider:

- In your 1800s game, the Time Traveler has access to items/allies from other time periods with unique abilities (both ancient relics and future tech)
- Perhaps the Time Traveler faces an event deck where other versions of your time-traveling self DO make contact from time to time. Sometimes you drops in to offer assistance (a free bonus), and other times you are looking for help (requiring an additional payment). Perhaps there could be some kind of track for how often you're able to fulfill these requests, which then powers up bonuses when you later show up to help yourself. In this scenario, maybe your character is still trying to invent the time machine and hence is at a chronologically stable point in life which makes this a great time for future versions to drop in, but this also gives the confidence that the invention will ultimately succeed.
- Consider more local time manipulation, such as spending time fuel to slow down time (gain extra actions or derive enhanced benefit from thematically having more time to focus on an action) or the ability to jump slightly ahead in time (perhaps skipping a phase of the game with negative consequences) Granted, these abilities don't really fit with H.G. Wells time travel narrative, but they could open up unique grok-able design space.
- Play up the ability to know/influence the future by allowing the Time Traveler to peek at and/or manipulate future results of random events (set die rolls, look at cards in a deck, or insert cards into a deck). Perhaps the game the rest of the players are playing IS the time traveler's past, and he/she is working towards a future outcome of which only he/she is aware (possibly involving repair of the time machine to go back to the future as a win condition).
- Focus more on how time travel could be used for practical outcomes, rather than actually having the player control the time jump itself. Need some extra money? Hop back in time and make a great investment or a high yield wager you know you'll win. Something break in a way that is difficult to repair or has someone fallen ill with an incurable disease? Jump to the future with all their fancy tech to patch things up. Mechanically, this could simply be spending your time-fuel for a direct resource advantage, but if the outcomes are something other players can't duplicate, it could still feel unique.
- I'm just going to throw this one out there. If the game features any kind of combat, an army of dinosaurs wouldn't be the worst thing in the world, would it? ;-)

Obviously, these ideas are going to make this feel less like a "time travel GAME", but if only a single faction is going to rely on time travel, right-sizing the complexity of these mechanics is probably key. In a multi-faction game, I think your greatest mileage for this type of faction will come from providing unique but easily comprehensible abilities which can be intuitively explained using the time travel tropes already bouncing around in your players' heads. I'm by no means an expert at Smash-Up, but I think the way they approached the time travel faction made a lot of sense within the system for their game (see https://smashup.fandom.com/wiki/Time_Travelers for a summary), and finding a similar fittedness to your game ought to be your goal, IMHO.

Good luck!