I think there is a (rough) trope within multi-species worldbuilding to include species in three (fairly broad) categories – The Warrior, The Brain and The Utility. Its also a gamebuilding trope to have three categories of player character – which often fit this Warrior, Brain and Utility triple.

Often species and classes actually end up as some sort of hybrid cross between these three concepts.

I think the origin of the trope is that worldbuilders and gamebuilders (new favorite word) are looking for ways to have their species differ from humans, without being some sort of uber-human. Therefore they need to find niches for their species relative to humans, and these three niches are the most obvious. Ancient and experienced Elves are really cool to have in game but (1) how do you play something so alien and (2) how do you balance something so experienced? You can do it, but its not easy.

I’ve compiled a few examples below. Often there are multiple entrants within a niche in more broadly built worlds. Sometimes I’ve written the name of a character when we only really see one member of a species. It’s a point in favour of the existence of this trope, that it sometimes occurs for just groups of characters not whole species.

Setting	The Warrior	The Brain	The Utility
The Lord of The Rings	Orcs/Uruk-Hai	Elves	Hobbits
Star Wars (1977)	Chewbacca	C3PO	R2-D2
Star Trek: The Next Generation	Worf	Data	Deanna Troi
Mass Effect	Turians/Krogan	Salarians	Asari
Warhammer 40k Officio Assassinorum	Eversor/Vindicare	Vanus	Culexus/Callidus
Farscape	D’Argo	Rygel	Zhaan
Wheel of Time Ajahs	Green/Red Ajahs	Brown/White Ajahs	Yellow/Grey Ajahs
D&D 5e	Half-Orc/Orc	Gnome/Elf	Half-Elf/Dwarf
The Inheritance Cycle (Eragon)	Urgal	Elf	Werecat

Okay so using Eragon is a bit of a cheat since it’s a composite of Star Wars and Lord of the Rings anyway but I think the point is being served.

Warhammer 40k doesn’t quite fit, but within each faction you’ll find examples of The Warrior, The Brain and The Utility, as evidenced by the 40k assassins. It’s just a matter of game balance really, most factions need to be able to do a variety of things.

Using (and inverting) this trope

It’s a good trope.

It provides distinction between in-world groups and between players.

It’s worth being aware of it and bearing it in mind when worldbuilding or gamebuilding (I’ve used it three times so that means it’s a real word now).

Invert the trope

A nagging voice at the back of my head

• No (or minimal) inherent specialisms
  • Some games do this – for example in Knave what you can do is based on your inventory, not a race or class
  • Continuum, the time travelling roleplaying game allows you to jump out to another time, take months learning a skill, then jump back and resume what you were doing. You’re spending your age to skill up, and everyone can learn new languages and skills.
  • Similarly, a game based on The Matrix would fit this because characters can download skillsets and just learn, for instance, kung-fu from a program. They are distinct due to their personality, destiny, fate and will.
• Mono-class (or archetype) campaigns
  • A campaign where every PC is a Wizard (or Fighter or Bard or what-have-you) would enable the party to solve certain problems really well, whilst struggling with others. Even with the (massive) variations you get with 5e subclasses, a group of Wizards will struggle with healing whilst a group of Barbarians will struggle with utility.
• Everyone is The Warrior
  • Games can (and do) differentiate between lots of types of warrior quite easily. From the top of my head there’s
  • The Brute
  • The Honourable fighter / The Fighter with a Code
  • The Ranged attacker
  • The Sneaky warrior
  • etc
• Everyone is The Brain
  • When I used to run Star Trek Adventures (which I once accidentally reviewed) the players had different competencies, but everyone was a brain. They could all find solutions to problems, or clues to mysteries with treknobabble in a way relating to their character. They were actually all the utility too. I think Star Trek actually has too much utility to be easily gameable, but that’s a post for another time.
• Everyone is The Utility
  • I’ve been working on-and-off for a while on a gamebuilding a magic school rpg. When its finished (if its finished) – everyone will be the utility, delineated by knowing different spells.
  • I’ve not played it but I understand that Mage: The Ascension fits this trope-inversion.
• The opening to The All Guardsman Party is a classic inversion of this trope. If an Ork WAAAGH! are going to kill you all in ten minutes, it doesn’t matter that much if one player is a bit more of a warrior than another.

Let me know of any others I can add to either this list or the table further up.