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