How many games should you play to test an Azuki TCG deck change?
Change one thing at a time, and judge it on what you saw rather than the record. Ten games show whether a new card gets played and does its job, but a deck that wins half its games can go 8-2 or 2-8 over ten by luck alone. A 5-point difference takes hundreds of games to see.
One time I went 7-3 and thought I was a genius. Then I went 3-7 with the SAME deck. Luck is so sneaky.
How to tell
- You change five cards at once, then cannot tell which one helped.
- A 6-4 week convinces you a swap worked.
Example: How far luck moves a 50% deck
A deck that truly wins half its games still lands anywhere in these ranges about 95% of the time:
| Games | Wins (95% of the time) | Win rate |
|---|---|---|
| 10 | 2 to 8 | 20 to 80% |
| 20 | 6 to 14 | 30 to 70% |
| 50 | 18 to 32 | 36 to 64% |
| 100 | 40 to 60 | 40 to 60% |
So test the things ten games can show: does the new card get played, does it come out on time, and does the loss you were fixing happen less.
How to fix it
- Change one card pair at a time: two copies out, two in.
- Play the new list against the same decks as the old one. In Practice you can pick the opponent’s deck.
- Watch the job, not the record: is the new card played, and does your most common loss happen less?
- Keep a change that clearly does its job. Revert one you never get to play.