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