Should I Have Multiple Alien Species or Just One?

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Hello again,

I was thinking about how some stories focus only on one type of being, like how Steven Universe has the Gems, whereas other stories, like Tolkien’s work, have many different types of beings. What I’m interested in finding out is, what are some of the pros and cons of each?

Thanks in advance!


Hey Tifa, great to hear from you again!

While the specifics vary from story to story, the trade-off between more and fewer fantasy elements is the trade-off of additional options for added complexity. This is true of all spec fic elements, not just non-human species, but let’s focus on that aspect of it today.

The more non-humans you add to the story, the more opportunities for novelty you have. Each fantasy species can be cool and different in a unique way, making your setting more interesting to readers. You also have more plot options, as non-humans create delicious opportunities for conflict, as well as storylines specifically about different species. Having elves in your world lets you tell a story about the fatigue of watching entire civilizations rise and fall, whereas adding dwarves means your plot can dig too greedily and too deep.

But with each new species you add, the world gets more complicated. There’s more for readers to remember and a greater chance of introducing exploitable combos that cause plot holes. You don’t have as much time to explore each non-human group, so there’s a risk that they become shallow tropes rather than a living species.

There’s a careful balancing act to be struck depending on how long your story is and how important the different groups are to your plot. In most cases, you don’t want a bunch of extra non-humans running around if they aren’t central to the conflict, as they then become just another set of details that readers have to remember, but for no real gain.

As a final note, Steven Universe plays a bit of trickery with the Gems. While they look like one species at first, the many different types of Gem allows the SU writers to get most of the same benefits they’d have if they included several different alien species. This is also why the Gems have so many different powers, some of which come back to haunt the show later. If Mythcreants had a dollar for every problem Team Steven could have solved with fusion, we wouldn’t need Patreon anymore.

We also have a few articles that touch on the subject, which you might find useful:

Hope that answers your question!

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  1. Rose Embolism

    This is an interesting question, in that having alien species can serve to open up a world and make it more complex and fantastical. It can open up entirely new issues as well.

    One thing to consider is there can be a difference between physically different aliens, and culturally different aliens. “Voyage to a Small Angry Planet” has aliens with a wide variety of body types, however they all pretty much share a recognizable culture. “Memory called Empire” on the other hand, features two groups of humans, but the Teixcalaan empire’s culture is very alien to that of Lsel station (and contemporary Western culture).

    Taken to an extreme, this leads to two problems to consider: the “humans with appliances” vs “race of hats” issue. One one hand, aliens end up being an excuse to have slightly different physical abilities, but are otherwise indistinguisbhable from humans. On the other, you get a race where all members of it are overwhelmingly defined by a trait (All Rhodians are hunters, all orcs are angry, etc.). It can be extremely difficult to come up with an alien that feels both believably different yet individual.

    The number one thing to ask is “Why aliens?” What do you want to do with them? Do you want them as cowardly yet incredibly advanced and manipulative patrons (Hello Puppeteers)? Do you want them as a rival for Humans and a bad Communism metaphor? (See Heinlen’s Bugs) Do you want them as indications that the universe is bigger and older and weirder than we can imagine (Winter Tide’s Deep Ones, Hoyle’s Black Cloud)? think of what the aliens mean for your setting, and the stories you want to tell in it.

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