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