Feng Shui has a similar temporal inertia concept, with a couple of neat twists

Firstly, only a certain number of time periods are accessible at any given time (currently these are the AD 70-ish, AD 1850-ish, AD 2007-ish, and 2060-ish - they were originally AD 69, AD 1850, the present day and 2057, but obviously time has moved on since the game was written).  These "junctures" are accessed through portals to and from a "Netherworld" that exists at all time periods at once

The game is all about control over the flow of chi though the world, particularly where it accumulates at what are known as Feng Shui sites.  The more sites under your control, the better "luck" you have and if you have sufficient sites under your control in a particular juncture then the future changes going forward from that juncture.  This is known as a Critical Shift and only people who have ever entered the Netherworld will notice that things have changed (in my current campaign I used a minor Critical Shift to give a PC an ex-wife and daughter he knew nothing about)

So you could go back to the 1850 juncture and kill Hitler's ancestors, but nothing would happen except perhaps he'd be called Hans instead.  But if you went back to the 1850 juncture, formed a power base, knocked over a few Feng Shui sites and killed Hitlers ancestors, then you might stop the rise of Nazism and your power base would have a significant effect on world history

You can leave messages or equipment caches for your future self, but the GM is encouraged to interfere if they would cause paradoxes or aren't dramatically appropriate.  A lot can happen in 150 years.  Receiving a box from a lawyer is a great way to start an adventure, but how do you know it's actually from "you" and not one of your enemies?

Ooh, i like the idea of inertia. Means that people really have to work at it, if they want to change future events. It also allows travelling for *adventure* or *exploration* to be carried out without as much fear of what your actions may cause further down the time-line. Cool.

Quote from: One Horse TownOoh, i like the idea of inertia. Means that people really have to work at it, if they want to change future events. It also allows travelling for *adventure* or *exploration* to be carried out without as much fear of what your actions may cause further down the time-line. Cool.

You got it.

The Time Corp has several branches, one of which is Research (which the PCs are currently in). Their job is simply to go to places in time and observe them. Combining Temporal Inertia with a variation on the Observer Principle, if they experience an event it becomes "more real" in the sense of harder to change. Of course, if what they observe is WRONG, that can lead to troubles too.

I rather like the way BTRC's TimeLords handles paradox.  In a rather complex, messy fashion that adds a certain feeling of versimillitude to the matter.  It involves some changes not propagating forward, the splitting off of timelines that either rejoin the main timeline, form their own separate timeline, or die off.  You get ripple effects, or self-correcting changes.  All in all, it gives the GM a lot of flexibility in addressing the issue when it arises.

When I get home, I need to dig out the book again.  I may be able to explain it better after I refresh my memory...

Tom B.

Quote from: Stumpydavehttp://www.aetherco.com/continuum/

Its had excellent reviews and one day I'll buy a copy. Probably yesterday.

Continuum goes into this stuff in dizzying detail, it's probably the most sophisticated treatment of time travel ever to see print in an rpg.

Not coincidentally, I know of nobody who has successfully run it, and it is not rules heavy.

Is that a challenge?

I challenge you to find a cooler word than "Continuum"

Two u's for gods sake.

Unless, of course, you prefer "Syzygy." No vowels and z!

Now back to your regularly scheduled discussion of the time travel paradox.

Zyzzyva. Nothing like a bunch of ten and four point letters to make your day (although two of them have to be blanks). And besides that, it's a weevil. Everyone loves weevils.

Qoph is a good one too. One of the few times you see a q not followed by a u. It's just a letter in the Hebrew alphabet and the sound the letter makes though, so nowhere near as sexy as zyzzyva.

I'm a big fan of Aa as well. Nice and symmetric.

Or perhaps your fish tank could use a lovely new humuhumunukunukuapua? It's the unofficial state fish of Hawaii.

Yes, I played lots of Scrabble as a kid, and read the Scrabble dictionary for fun. No, I'm not overly competitive, and if you don't believe me we can arm wrestle for it. Although if you're really muscular I'd suggest we Boggle for it instead.

An old one is Chronomancer for AD&D2. Thing is, it was designed and developed for Mayfair Games' Roleaids line originally, and came into TSR's hands with the legal settlement between the two companies. So TSR decided to get something back for all that money they spent and published it. Shaman for AD&D2 was much the same deal.

Quote from: BalbinusContinuum goes into this stuff in dizzying detail, it's probably the most sophisticated treatment of time travel ever to see print in an rpg.

Not coincidentally, I know of nobody who has successfully run it, and it is not rules heavy.

I keep holding on selling the book. I've had it forever and tried to absorb the whole thing a few times but failed. It just hasn't been fun to read and the mechanics don't appear all that nifty either.

Yet it has received high praise at times. Enough for me not to sell.

I really have no excuse and should just give it a try soon.