Getting the Most Out of Your Theme
Make things relatable. Relatability is where something in your game evokes something the player is already familiar with. The player can relate to the item, event, or character, and they can feel like they're really in the story.
Known things
Your game objects should represent things the player already knows. You give a card or object a relatable name (and later, the publisher does matching artwork.)
However, this is only half the picture. The object has to actually behave like the real thing. The mechanics must match the theme/name of the object.
Radlands is full of such cards. There's Wounded Soldier — an excellent warrior, who starts out damaged, and you have to heal him, if you want to use him. Cult Leader sends your other people off to their doom, to destroy the opponent's stuff. Catapult lets you hurl your own people. In game terms, it destroys one of your people, and can hit anything. This matches the theme closely.
Connecting theme and function is key to immersive gameplay. If you can't do this, because your game rules are too simple, it means you need a smaller and less pretentious theme.
Also, a relatable card or item isn't just cool, it also helps people understand gameplay. A new player might be introduced to a lot of new things, but if those things work in obvious ways, it will be much easier for them to remember. An axe that cuts down trees, and gains you wood, is relatable. The Charm of Kroznor that swaps two resources, is not relatable. (Be careful not to get it mixed up with the Charm of Grozbat, which rearranges the top four cards of the deck!)
A useable theme
Most things in your game should be entities: people (or characters), places, and objects. These categories are full of well-known and relatable things.
I do use actions, events, states of mind, etc, but in smaller numbers. They're much harder to make relatable and distinct. It's also harder for artwork to clearly depict them.
In Lords of Waterdeep, you gather adventurers, and complete quest cards. These quests are unrelatable nonsense like "Protect the House of Wonder" and "Establish Harper Safe House". I would've themed these to be different monsters that you fight, not "quests".
In my gangster game, I gave each player a "Big Dreams" card, which was a unique and expensive thing that only they could do. I later changed this to each player having a "criminal profile". They could be a catburglar, a biker, a scientist etc. These were people, and they were much more relatable.
I've played many game prototypes about elemental magic duels. Everything is some variety of abstract spell of some sort, and it's all meaningless.
In Star Realms and Space Base, the cards are spaceships. Each card's theme only loosely relates to its mechanics. They have no character, and they all seem similar.
Wingspan is a hugely successful game about birds. However, it's just a pretty theme. It's almost impossible to connect hundreds of different birds to their abilities. What's a Canvasback anyway? (Seemingly some kind of duck.) And why is its ability "all players draw a card?"
Names
I don't like creative names.
Radlands uses very simple names like Scientist, Exterminator, Holdout, Sniper, Arena, and Blood Bank. These names all tie in closely to the actual function of the cards.
Some names have to be strange, because there's no simple and good name that matches the function of the card (or other game object).
However, my policy is that as many names as possible should be a "real thing". This could mean something that exists in the real world (like Catburglar, Mosh Pit, or Flamethrower.) This could also mean a known fictional thing (like Portal, Time Travel, or Magic Wand.)
The Radlands expansion had a card called "bivouac". Unfortunately, half my playtesters didn't know that word. Some even thought it was "bio-vac". It had to change.
If a name is two words, they should be a known phrase, not simply adjective-noun. (Rabid Dog and Fuel Tanker are good. Silver Axe and Immortal Angel are not.)
Also, work backwards from the theme. Come up with the best-known and most thematic characters, items and events, from the theme of your game. Then, make cards for them.
Magic made sets of cards set in a gothic horror world. They filled these sets with cards designed backwards from the theme. The set was full of relatable cards like Bump in the Night, Cellar Door, Boarded Windows, and Jar of Eyeballs. They introduced double-sided cards, so that some townsfolk cards could "flip over" to a werewolf side at night.
In other sets, Magic cards were just random two-word names, as every name had to be unique. No one knew who the Woodland Acolyte was, and who was the Forest Harbinger. I saw many new players simply ignore this nonsense, and read the type line e.g. Creature — Elf Warrior, instead.
Not everything has to have a name. Very simple decks of resource cards, or other highly abstract things, do not all need names. If you're struggling to name things, then they may not need names at all.
In Wingspan, there are dozens of objective cards you can draw. You reveal them at the end, and if you meet the criteria, you get some points. Some of these have sensible names, but many are a stretch. "Citizen Scientist" gives you points for having bird cards tucked under your other birds. Mechanical Engineer gives you points for having sets of different nest types. What? Also, they have no art.
In my farm game, I also have these kinds of goal cards. I intentionally have no art or names on these cards—just icons and numbers of the resources required. To name the 3 Wood card "cut down a tree" is nonsensical visual clutter. It's better to just have these things be themeless. Board spaces, on the other hand, do have names, as it helps connect the theme and function of the space, and they actually make sense.
Proper names
For proper names of characters and places, the name should:
- Have obvious pronunciation.
- Be short.
- Be clearly different from each other.
In Radlands, I included characters Magnus Karv, and Molgur Stang. Those first names are too similar, and players can find them hard to differentiate.
Flavour text
Flavour text is a bit of story or information at the bottom of a card, that has no impact on gameplay.
For heavily theme-driven games, and real-world and real historical settings, flavour text is a good idea. Otherwise, it's usually irrelevant. I don't want to hear about the great war between the Earth and Water tribes.
Radlands was too mechanical, and the players see the same cards all the time, so flavour text would've been boring.
For my gangster game, flavour text let me add humour to the game. For my adventure game, which is even more theme-driven, it let me tell interesting stories.
Theme bending
Don't be hemmed in by your theme. If you need to do something for mechanical reasons, just do it. You can make anything work, thematically. Theme is important, but much less important than mechanics.
Some themes are inherently single-player (or cooperative.) If you're exploring a land, or going on a journey, for instance, how is this a competitive game?
I made a game where the players were trying to survive as shipwrecked castaways. That's an amazingly relatable theme, in my opinion.
I didn't want the mechanic of the players helping each other, so I made the castaways criminals. I didn't want player elimination, so I just decided that you would lose points if you failed to sustain yourself, rather than die. But what was victory, in this game? I decided that the player who survived this experience best (by having the most points at the end) was the winner. This was all a bit strange, but none of it impinged on the feeling of being a castaway, which was well-supported by the other game elements.