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