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