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for a gold chocobo?

you'll need a male and female for starters

good and great for starts
IIRC

Good-Gold Saucer area
Great-Mideel

one male one female and race them to Rank A or S perferrably S, it should only take about 10 wins or so

Next breed them with a Carob nut, picked up after battle w/ that red dino thing on the area near Bone Village

You'll get either Green or Blue, then you have to repeat the process for the other color

Next race Green and Blue to rank A or S and bread w/ a carob nut again

you'll have a black chocobo now.

catch a Wonderful choc. on the tracks outside of Icicle Village

race each black and wonderful to Rank S and breed w/ a Zeio Nut, won after battle w/ Goblins on Goblin Island, and youll have a gold chocobo

any questions?

u dont need a or s rank chocobos to get them, it only increases the chances.i got em at like b class or so.