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