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