Here is the full list of all 232 The Great Gaias achievements.
Complete Chapter I.
Complete Chapter II.
Complete Chapter III.
Complete Chapter IV.
Complete Chapter V.
Complete Chapter VI.
Acquire Bruger the Barbarian as a party member.
Acquire Virgil the Wizard as a party member.
Acquire Kaelas the Druid as a party member.
Acquire Elric the Ranger as a party member.
Acquire Laeni the Priestess as a party member.
Acquire Griswold the Cleric as a party member.
Acquire Wein the Paladin as a party member.
Acquire Quathorn the Conjuror as a party member.
Acquire Furi the Sorceress as a party member.
Acquire Agramed the Gladiator as a party member.
Acquire Valdraek the Spellsword as a party member.
Acquire Atrius the Assassin as a party member.
Acquire Caelia the Alchemist as a party member.
Acquire Hiro the Dragoon as a party member.
Acquire Belkas the Fighter as a party member.
Acquire Adelle the Engineer as a party member.
Achieve Level (65) with Pots.
Achieve Level (65) with Bruger.
Achieve Level (65) with Kaelas.
Achieve Level (65) with Elric.
Achieve Level (65) with Laeni.
Achieve Level (65) with Griswold.
Achieve Level (65) with Wein.
Achieve Level (65) with Quathorn.
Achieve Level (65) with Furi.
Achieve Level (65) with Agramed.
Achieve Level (65) with Valdraek.
Achieve Level (65) with Atrius.
Achieve Level (65) with Caelia.
Achieve Level (65) with Hiro.
Achieve Level (65) with Belkas.
Achieve Level (65) with Adelle.
Help the Archaeologist with a new discovery at the Farlen Dig Site.
Become the Guildmaster of the Veil of the Black Hand.
Ascend Furi Stormcrow to the Circle of Twelve.
Become the World Champion in the Osirian Gladiator Arena by defeating Agramed.
Build the Normal City.
Build the Vagrant City.
Build the Noble City.
Build the Merchant City.
Build the Religious City.
Build all versions of the Build Your Own City sidequest.
Acquire Dawnbringer.
Acquire Quicksword.
Acquire Oni Glove.
Acquire Osiluth's Axe.
Acquire Earthen Staff.
Acquire Ascalon.
Acquire Longinus.
Acquire Void Axe.
Acquire Anima.
Acquire Hadriel's Dagger.
Acquire Caladbolg.
Acquire Muramasa.
Acquire Callandor.
Acquire Staff of Force.
Acquire Larnaen Bow.
Acquire Ethereal Veil.
Acquire Warmage's Robe.
Acquire Rogue Cap.
Acquire Shadow Leather.
Acquire Stablemaster's Coif.
Acquire Jormerys' Hauberk.
Acquire Tanzite Helm.
Acquire Tanzite Armor.
Acquire Aegis Shield.
Acquire Mirror Shield.
Acquire Flintlock.
Acquire Courtain.
Acquire Sauvagine.
Acquire Vandar's Veil.
Acquire Vandar's Vestments.
Acquire Vandar's Gauntlets.
Acquire Silverspark.
Acquire Ulgar's Cuirass.
Acquire Ulgar's Crown.
Acquire Ulgar's Bracers.
Acquire Caduceus.
Acquire Windspeaker's Hood.
Acquire Windspeaker's Robe.
Acquire Periapt of Benevolence.
Acquire Rhonghomiant.
Acquire Herald of Tantalasia.
Acquire Arthur's Helm.
Acquire Silver Armor of Tantalasia.
Acquire Scarab of Protection.
Acquire The Rod of Arman.
Acquire Evalache.
Acquire Arman's Helm.
Acquire Arman's Plate.
Acquire Sigil of Arman.
Acquire Oathbow.
Acquire Helm of Highwater.
Acquire Elvandor's Armor.
Acquire Quiver of Artemis.
Acquire Fists of Raziel.
Acquire Amon'Quel's Hood.
Acquire Amon'Quel's Robe.
Acquire Ring of Amon'Quel.
Acquire Staff of Magi.
Acquire Ioun Stone.
Acquire Veriel's Robe.
Acquire Zacharael's Sash.
Acquire Arethid.
Acquire Harpe.
Acquire Osiluth's Helm.
Acquire Osiluth's Spaulders.
Acquire Gjallarhorn.
Acquire Masamune.
Acquire Saarinen's Helm.
Acquire Saarinen's Hauberk.
Acquire Saarinen's Belt.
Acquire Heron Blade.
Acquire Veil of Atreyu.
Acquire Atreyu's Doublet.
Acquire Sigil of Althorand.
Acquire Olto's Dagger.
Acquire Hezerac's Buckler.
Acquire Hezerac's Hood.
Acquire Hezerac's Garb.
Acquire Hezerac's Vial.
Acquire Atgeir.
Acquire Raenor's Targe.
Acquire Raenor's Helm.
Acquire Raenor's Plate.
Acquire Raenor's Mantle.
Acquire The Ender.
Acquire Gerald's Helm.
Acquire Gerald's Plate.
Acquire Gauntlet Locks.
Defeat Amon'Quel at Arman's Tower.
Defeat Raziel at Greyhem.
Survive Zacharael's assault at the Tower of Amon'Quel.
Defeat Belkas and company in his home at Miner's End.
Defeat Ledonel at the Tower of Horror.
Defeat the Stonewalls.
Defeat Belkas and company on the outskirts of Porthul.
Defeat Azrael at Solstice.
Defeat Israfel at the Valpheggi Swamplands.
Defeat Zacharael at Arad Munlo.
Defeat Omniel at Ilbed.
Defeat Belkas and company outside Malgoraxia's Cave.
Defeat Hadriel during the Battle on the Airship.
Defeat Sammael at Sovereign.
Defeat Belkas and company at the Battle of Greyhem.
Defeat Adramelech at Greyhem.
Survive Adramelech's assault at the Battle of Greyhem.
Defeat Larienael at Xelloss.
Defeat Veriel at the Island Generator.
Defeat Eldromus Blackheart at the Emperor's Palace.
Defeat Cael Vaeili in the South Tower at Farlen.
Defeat the Omnimental at the summit of Mount Ortis.
Defeat Hallenden.
Defeat the Watcher in his Apothecary.
Defeat Khargynoth in the Temple.
Defeat Malviticus in the Celestial Realm.
Collect (1) Celestium Shard.
Collect (10) Celestium Shards.
Collect (20) Celestium Shards.
Collect (30) Celestium Shards.
Collect (40) Celestium Shards.
Collect (50) Celestium Shards.
Collect (60) Celestium Shards.
Collect (70) Celestium Shards.
Collect (80) Celestium Shards.
Collect (90) Celestium Shards.
Collect (100) Celestium Shards.
Collect (110) Celestium Shards.
Defeat the Kraken out of the port of Dupre.
Return the family heirloom of Gavin Rems.
Save Tommen and his men in the Mythril Mine.
Defeat the Necronaut in the Tower of Horror.
Save Diarmud from the Dragon Hunters in Greybridge.
Find a new home for the Madurai in Alme.
Restore the light to the island of Farlen
Restore Korin Faelyn as the rightful King of Amanor.
Return the holy land of Ghar Jalal to the Osirians.
End the persecution of the Spellswords in the Plains of Zaardun.
Defeat Pale Night at the Tomb of Atzantiel.
Unite the Clans of Frosthammer under a new High Thane.
Stop the warring Kingdoms at the Battle of Greyhem.
Achieve an appointment on the Circle of Twelve.
Defeated the Validian Empite at the Battle of the Blighted Lands.
Raise Mining Skill to (10).
Raise Mining Skill to (20).
Raise Mining Skill to (30).
Raise Mining Skill to (40).
Raise Mining Skill to (50).
Raise Mining Skill to (60).
Raise Mining Skill to (70).
Raise Mining Skill to (80).
Raise Mining Skill to (90).
Raise Mining Skill to (100).
Raise Disable Device Skill to (10).
Raise Disable Device Skill to (20).
Raise Disable Device Skill to (30).
Raise Disable Device Skill to (40).
Raise Disable Device Skill to (50).
Raise Disable Device Skill to (60).
Raise Disable Device Skill to (70).
Raise Disable Device Skill to (80).
Raise Disable Device Skill to (90).
Raise Disable Device Skill to (100).
Raise Lockpicking Skill to (10).
Raise Lockpicking Skill to (20).
Raise Lockpicking Skill to (30).
Raise Lockpicking Skill to (40).
Raise Lockpicking Skill to (50).
Raise Lockpicking Skill to (60).
Raise Lockpicking Skill to (70).
Raise Lockpicking Skill to (80).
Raise Lockpicking Skill to (90).
Raise Lockpicking Skill to (100).
Acquire a Stone Mortar and Pestle.
Acquire a Copper Mortar and Pestle.
Acquire a Silver Mortar and Pestle.
Acquire a Gold Mortar and Pestle.
Acquire a Platinum Mortar and Pestle.
Acquire Hanzo, the Lord of Blades.
Acquire Leviticus, the Lord of Ice.
Acquire Kraxus, the Lord of Constructs.
Acquire Leviathan, the Lord of Water.
Acquire Raijin, the Lord of Thunder.
Acquire Thanatos, the Lord of Death.
Acquire Uruboros, the Lord of Space.
Acquire Kronos, the Lord of Time.