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