Pulled from:
http://www.gamefaqs.com/console/psx/file/197343/10404Save outside town. When you enter Dollet, you'll see two girls standing
at the car rental place. Challenge the one on the left to cards.
She will say, "So like, you seem to know rules unfamiliar to this region.
So like, let's play a game with Galbadia's rules and ours." (meaning Mix
rules?)
You say Yes.
Now the rules will appear (Open, Random, Elemental, Same, and the trading
rule).
Choose Quit (quitting allows you to combine and change rules without
having to play so many games, and, in this instance, you don't risk your
rare cards to the Random rule).
After a hand or two, you should get the message "Open has spread to this
region." If she quits asking to mix rules and you never got a message,
reset and try again. It shouldn't take long to spread Open. If you happen
to get a message saying "Random (or Elemental) was abolished from this
region," even better, but this rarely happens. As soon as Open spreads,
go outside and save.
To change another rule in Dollet, we must go in with a rule they don't
have (Same), so we'll run to Timber. If you stay on the road, you won't
encounter any enemies. When you enter Timber, you'll see two guards at
the front gate. Challenge the one on the left.
He'll say, "You seem to know rules unfamiliar to this region. Let's play
a game with Dollet's rules and ours."
Say NO. Remember, the secret to manipulating rules is to never spread any
rule except Open (which we've already spread in Timber/Galbadia). This
man will probably suggest that you mix rules several times. Say NO every
single time, and eventually he'll just say, "How about a game of cards?"
Say Yes. When the rules come up (Open and Same), you can either quit or
play. It's up to you.
Now head back to Dollet. Save outside before you go in and go challenge
the same girl to a game. Follow the exact same procedure you did before:
"Galbadia's rules and ours?"
Yes.
Quit.
There are five possible outcomes here:
"Open was abolished from this region."
"Random was abolished from this region."
"Elemental was abolished from this region."
"Same has spread to this region."
Nothing happens.
You are interested only in Random and Elemental. If any of the other
three occur, reset and try again. DO NOT abolish Open and DO NOT spread
Same. Just keep at it until either Random or Elemental is abolished. Now
go outside and save again. Don't become discouraged. Of all the players
I've tried in Dollet, this girl changes rules the most readily, but it
can still take time. Which rules spread or abolish is random, so you just
keep resetting until you get the one you want.
After ridding Dollet of Elemental or Random and saving outside, head to
Timber one last time. Keep saying No to the guard until you're carrying
Timber's rules of Same and Open.
Return to Dollet, save outside, and challenge the girl again. Mix, Yes,
Quit (resetting as you need to) until you abolish that last rule. Go
outside and save.
Congratulations! You have just established Open as the only card rule in
Dollet, and you just made your life and the Queen of Cards quest much,
much easier.