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.
Receive 30 back attacks.
Win 10 items at the Treno Auction House.
Defeat 1000 enemies.
Summon Eidolons 50 times.
Play the blackjack minigame.
Complete FINAL FANTASY IX.
Defeat Lich, the Guardian of Earth.
Obtain the Mace of Zeus.
Defeat Kraken, the Guardian of Water.
Synthesize 30 items.
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.
Form a party with four male characters.
Form a party with Quina Quen and three female characters.
Summon the eidolon Ark.
Defeat Ozma.
Receive certification as a Rank S Treasure Hunter.
Obtain the sacred blade Excalibur.
Obtain the Hammer.
Receive 10 rewards from Queen Stella.
Defeat Behemoth in the Treno weapon shop using Dagger.
Purchase all items available from Stiltzkin.
Attain level 99 with at least one character.
Obtain 4 moonstones.
Obtain the Ultima Weapon.
Use White Magic spells 200 times.
Summon the eidolon Ifrit.
Summon the eidolon Shiva.
Summon the eidolon Leviathan.
Summon the eidolon Atomos.
Summon the eidolon Bahamut.
Summon the eidolon Odin.
Correctly answer all the questions in Ragtime Mouse's pop quiz.
Gain the favor of all friendly enemies.
Summon the eidolon Madeen.
Enter trance 50 times.
Activate the Rebirth Flame ability when all party members are incapacitated.
Locate all hidden treasures on the world map.
Obtain an airship.
Obtain the complete set of Genji armor.
Successfully catch a golden frog.
Obtain the Tiger Racket.
Obtain the Whale Whisker.
Raise your chocobo's beak level to 99.
Use Blue Magic spells 100 times.
Use Black Magic spells 100 times.
Summon the eidolon Phoenix.
Summon the eidolon Carbuncle.
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.
Summon the eidolon Fenrir.
Summon the eidolon Ramuh.
Synthesize 10 items.
Obtain Madain's Ring via mining.
Free Kuppo from a wall in Fossil Roo.
Use the Defend command 50 times.
Guide all the residents of Cleyra to safety.
Win with Vivi during the Festival of the Hunt.
Receive a Very Good Omen from a color fortune.
Cause Moguo to have a tantrum.
Defeat 100 enemies.
Use the Steal command 50 times.
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.
Uncover the secret of the Eidolon Wall.
Visit every beach in Gaia.
Repair the machine at Mognet Central.
Obtain a bottle of Superslick.
Successfully catch 99 frogs.
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.)
Have a single character affected by all status ailments. (both beneficial and detrimental).
View 79 Active Time Events.
Obtain the Gastro Fork.
Obtain Excalibur II.