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