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