Here is the full list of all 85 Final Fantasy IX achievements. It takes around 80-100 hours to unlock all of the achievements on Windows.
Win 100 Tetra Master matches. (Certain NPCs can be re-challenged to increase your win count after progressing through the game.)
Defeat 10000 enemies.
Defeat 1000 enemies.
Receive 30 back attacks.
Obtain the Gastro Fork.
Successfully catch 99 frogs.
Win 10 Tetra Master matches.(Certain NPCs can be re-challenged to increase your win count after progressing through the game.)
Defeat Ozma.
Activate the Rebirth Flame ability when all party members are incapacitated.
Have a single character affected by all status ailments. (both beneficial and detrimental).
Form a party with Quina Quen and three female characters.
Acquire all available support abilities.
Summon the eidolon Madeen.
Summon Eidolons 50 times.
Use Blue Magic spells 100 times.
Use White Magic spells 200 times.
Uncover the secret of the Eidolon Wall.
Defeat Behemoth in the Treno weapon shop using Dagger.
Visit every beach in Gaia.
View 79 Active Time Events.
Gain the favor of all friendly enemies.
Raise your chocobo's beak level to 99.
Beat the Nero Brothers' shuffling game nine times in a row.
Receive a Very Good Omen from a color fortune.
Cause Moguo to have a tantrum.
Play the blackjack minigame.
Obtain Excalibur II.
Form a party with four male characters.
Win with Vivi during the Festival of the Hunt.
Attain level 99 with at least one character.
Complete FINAL FANTASY IX.
Use Black Magic spells 100 times.
Defeat Lich, the Guardian of Earth.
Obtain the Mace of Zeus.
Defeat Kraken, the Guardian of Water.
Summon the eidolon Ark.
Defeat Tiamat, the Guardian of Wind.
Obtain the Rune Claws.
Obtain the Angel Flute.
Defeat Maliris, the Guardian of Fire.
Obtain the Tower.
Obtain Kain's Lance.
Repair the machine at Mognet Central.
Obtain a bottle of Superslick.
Purchase all items available from Stiltzkin.
Obtain 4 moonstones.
Obtain the Ultima Weapon.
Obtain the Hammer.
Receive 10 rewards from Queen Stella.
Obtain the sacred blade Excalibur.
Synthesize 30 items.
Summon the eidolon Bahamut.
Enter trance 50 times.
Summon the eidolon Leviathan.
Summon the eidolon Odin.
Receive certification as a Rank S Treasure Hunter.
Locate all hidden treasures on the world map.
Obtain the complete set of Genji armor.
Correctly answer all the questions in Ragtime Mouse's pop quiz.
Obtain an airship.
Summon the eidolon Atomos.
Summon the eidolon Ifrit.
Summon the eidolon Shiva.
Summon the eidolon Phoenix.
Summon the eidolon Fenrir.
Summon the eidolon Carbuncle.
Obtain the Tiger Racket.
Obtain the Whale Whisker.
Obtain a miniature copy of the Prima Vista.
Win 10 items at the Treno Auction House.
Obtain Athlete Queen.
Obtain Madain's Ring via mining.
Free Kuppo from a wall in Fossil Roo.
Summon the eidolon Ramuh.
Guide all the residents of Cleyra to safety.
Use the Steal command 50 times.
Use the Defend command 50 times.
Successfully catch a golden frog.
Synthesize 10 items.
Defeat 100 enemies.
Enter Trance for the first time.
Have the nobles demand an encore.
Win a Tetra Master match.
Jump rope 1000 times without tripping and obtain King of Jump Rope.
Jump rope 100 times without tripping.