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GameMastery Guide / Creating a World

Parallel Words

Source GameMastery Guide pg. 168
In physics, a theory called the “many-worlds interpretation” asserts that for any given choice or event, a separate reality is created for each possible outcome. Under this model, history is not a straight line but rather an endlessly branching tree, in which the viewer is only conscious of the limb he’s standing on (though alternate versions of him exist on other branches).

Alternate realities give GMs an unlimited sandbox in which to create new adventures for their players. Bored with your current setting, or its natural laws? Throw your party into a new dimension, one so strange that it’s an adventure just surviving, or so similar that the players only slowly come to understand what’s happened. Whether it’s a dream world, an alternate history, a parallel dimension, or some entirely new creation, alternate realities offer possibilities unavailable anywhere else.

Creating a Parallel World

Source GameMastery Guide pg. 168
To create an alternate reality, simply take the existing world and change any one event or factor, past or present. From that point, it’s a matter of extrapolation, tracing down the many routes that history could take given your change and picking the resulting world that seems like the most fun to play in.

For example, let’s say you want to create a parallel world in which the evil wizard-king, a recurring antagonist in your campaign, was never born (or better yet, was killed early on in his career by alternate versions of the PCs). Upon entering the world and discovering its difference, the PCs may initially rejoice. Yet perhaps they haven’t ever stopped to consider that, without the strong king to hold things together, his many dukes and barons would launch a war of succession that would kill thousands. Perhaps wizardry has been outlawed by zealots determined to never suffer such oppression again, and even good-aligned wizards are burned at the stake. And can the farmers and townsfolk defend themselves from monsters without the harsh but effective royal guard? Any time you make a change to your world, ask yourself what could go right, and what could go wrong—many times, the best challenges come from changes that, on the surface, seem positive. In this example, not only have you created a new world for your PCs, but you’ve also forced them to revise some of their basic beliefs.

While for most games it’s not necessary to explain the theory behind a parallel universe, such considerations can be fun for you as a GM. Did some cataclysm tear reality in two, creating parallel worlds evolving separately? Is it a naturally occurring phenomenon, or intentionally caused by some great wizard? Perhaps spells like wish create alternate realities to accommodate the caster’s flagrant breach of probability. All of these are academic questions, except for one: how to travel between the worlds. If you want to create a magical or scientific portal for your PCs to jump through, and follow it with another allowing them to return home, that’s perfectly valid. Yet you may want to make jumping between realities more complicated, the better to lead your party on quests and adventures, and to this end it helps to know the underlying structure of your realities.

As mentioned above, one model is to think of reality as a tree, with the PCs marking the end of a given branch. Every choice, event, natural law, or other discernible characteristic for its timeline has caused a branching, and the seemingly linear path back to the tree’s root is their history. Yet while that route is all they can perceive, every road their world didn’t take exists alongside them in the tree’s canopy, just waiting for them to jump between branches. As with an actual tree, those realities that branch closest to the PCs’ end point are easiest to reach—a world in which the events of yesterday turned out differently is comparatively easy to jump to compared to a world in which the PCs’ home nation was never founded, and the latter might require more powerful magic or a series of jumps through interstitial realities. This model also reinforces one piece of GM advice: while it may be tempting to alter a number of factors in your world at once, the ramifications of a single change are usually more than enough to keep you busy, and changing too many runs the risk of overwhelming your players. Keeping the worlds’ point of divergence identifiable is half the fun of alternate realities.

Sample Parallel Worlds

Source GameMastery Guide pg. 168
The following are several alternate reality archetypes. Of course, these are just a smattering of different possibilities to get you thinking—literally any world you could want to play in is possible using the parallel world model.

Time Travel: Moving up and down the timestream offers PCs a glimpse of the future or a chance to observe (and possibly change) important moments in history. By far the most fun and frustration involved with time travel, however, comes from paradoxes and the unintended consequences of PC actions. If they’ve gone to the future, does their foreknowledge make it possible for them to prevent that future—and if so, have they retroactively made it impossible for themselves to have visited it? What if they bring something back, introducing it to the world before it’s even been invented? Traveling into the past is even more dangerous, as the PCs have no idea which actions will have major repercussions farther along the timestream. From accidentally preventing her parents’ wedding to stepping on the prehistoric bug that eventually evolves into an intelligent species, there’s no end to the trouble a PC dabbling in chronomancy can cause, and the return home from a visit to the past is a perfect time to introduce an alternate history setting.

Alternate History: This term usually refers to a world in which a single historical event of some importance doesn’t occur, or plays out differently than in the PCs’ own timeline.

Mirror Universe: Popularized in modern science fiction, a mirror universe can range the spectrum from a literal realm of reflected doppelgangers (including opposite-al ignment versions of PCs) to a surreal Alice-style Wonderland. For a different take on this idea, try creating a world in which the gods have different alignments— forcing PC worshipers into conflict or converting them as well—or changing the alignments of a few key NPCs.

Superpowered: A world in which the PCs acquire godlike powers can be a lot of fun, though they might be surprised by the jealousy they suddenly inspire. These superpowers might be genuine new powers, acquired mysteriously in their transition between worlds, or it might simply be that some of the PCs’ normal abilities are unique to their new world, as no one there has ever encountered a monk’s slow fall ability or a bard’s magical songs.

Different Dominant Species: Whether it’s cities of peaceful, surface-dwelling drow or hyper-intelligent dinosaurs that never suffered mass extinction, a new dominant race in a world otherwise identical to the PCs’ own can present PCs with a host of challenges.

Different Campaign Setting: An alternate reality is the perfect chance to move existing characters between campaign settings. Always wanted to see how the barbarian would fare in Victorian-era England, or run the party through a far-future space opera? This is your opportunity to make your characters track down a Great Old One in 1800s New England, or to trade in your classic fantasy for post-apocalyptic mercenary work.

Different Natural Laws: The most fundamental change you can make to your world is altering the natural laws on which it runs. Though revising gravity might be too extreme, what about a world in which magic simply doesn’t work, or spells work in unexpected ways? Similarly, what about a world in which all the gods are dead—or weirder yet, never existed in the first place? Making such changes can be dangerous to the balance of the game—after all, few spellcasters enjoy losing their abilities entirely—but when done correctly, a world that’s identical save for the loss of magic, deities, or some other crucial constant can be more terrifying than any dungeon.

Going Home

Source GameMastery Guide pg. 169
While it’s possible that your players may fall so deeply in love with your parallel universe that they don’t want to go home (in which case, you now have a new campaign setting!), for most dimension-hopping adventurers, the whole point is to finally return to the world of their birth. Yet this homecoming doesn’t have to mean the end of the madness. For instance, how do the characters know they’re actually home? After letting the party breathe a sigh of relief, try placing some doubt in their minds, little inconsistencies that might indicate that they’ve only returned to a similar world, not their true home. If the front stairs to the characters’ favorite tavern no longer creak, is it because someone fixed them while the party was away—or because they never creaked at all?

Of course, extradimensional paranoia is only one way to have fun with the characters’ homecoming. Others are more blatant—for instance, if time doesn’t pass at the same rate between dimensions, the PCs might return home to a world 30 years after than they left it, during which time they’ve been vilified for abandoning their responsibilities. Once you’ve opened the door to parallel worlds, you’ve given yourself carte blanche to play fast and loose with your world and your players’ expectations, and nothing will ever again be quite what it seems.