To create a solid playable game using the flip-a-card system, I'd probably want about 70 cards, broken down more or less like this:
- 6 rule cards, covering the situations outlined here - how to adjudicate tests, whether there is a GM, and so on.
- 24 character cards, divided into three categories - e.g. heritage, role, and drive, as described here - with eight cards each. That gives 512 unique combinations of character cards, while only asking players to make three starting choices.
- 8 condition cards, indicating injury, pursuit, and whatever other problems the PCs are dealing with.
- 16 challenge cards, e.g. Kobold, Bandit, Dragon, Snowstorm, describing different situations or opponents the party might face.
- 16 challenge modifiers, e.g. Armored, Eldritch, Mysterious, each with their own guidelines or rules, that change how a given challenge works.
How much of this is reusable across games?
- Most or all of the challenge modifiers can be reused for games in the same or similar genre, e.g. Armored works whether you're talking about a hulking ogre or a WW2 tank.
- Most of the condition cards, again depending on genre.
- Any character cards that describe motivation or similar commonalities, e.g. Curious or Greedy.
If the cards are even 50% reusable, that's only 35 cards a new game creator must produce, and such cards can be produced by experienced players too.