Here is the full list of all 48 THRONE AND LIBERTY achievements worth 1,000 gamerscore.
Complete Codex "Island of the Star Children"
Complete Codex "The Tragedy of the Casill Family"
Complete Codex "The Demise of the Gray-Fanged"
Complete Codex "Veterans Never Die"
Complete Codex "The Terrific Trio of Carmine Forest"
Complete Codex "A Sacred Pledge of Blood"
Complete Codex "The Song of the Vienta Dwarves"
Complete Codex "The Sandstorm Overlord"
Complete Codex "The Demon's Smile"
Complete Codex "A Pact of Fire and Darkness"
Complete Codex "Nightmare Déjà Vu"
Defeat "Morokai"
Defeat "Excavator-9"
Defeat "Chernobog"
Defeat "Talus"
Defeat "Malakar"
Defeat "Cornelius"
Defeat "Adentus"
Defeat "Grand Aelon"
Defeat "Ahzreil"
Defeat "Minezerok"
Defeat "Aridus"
Defeat "Nirma"
Defeat "Kowazan"
Defeat "Junobote"
Defeat "Tevent"
Defeate "Queen Bellandir"
Claim the final rewards from Dimensional Circle "Specter's Abyss"
Claim the final rewards from Dimensional Circle "Roaring Temple"
Claim the final rewards from Dimensional Circle "Cave of Desperation"
Claim the final rewards from Dimensional Circle "Death's Abyss"
Claim the final rewards from Dimensional Circle "Cursed Wasteland"
Claim the final rewards from Dimensional Circle "Temple of Slaughter"
Claim the final rewards from Dimensional Circle "Butcher's Canyon"
Claim the final rewards from Dimensional Circle "Tyrant's Isle"
Claim the final rewards from Dimensional Circle "Cave of Destruction"
Participate in Dynamic Event "Wolf Hunting Contest" at Blackhowl Plains
Participate in Dynamic Event "Starlight Stones Ritual" at Urstella Fields
Participate in Dynamic Event "Lantern Seed Festival" at Nesting Grounds
Participate in Dynamic Event "Hidden Brown Mica" at the Abandoned Stonemason Town
Participate in Dynamic Event "Desert Caravan" at Moonlight Desert
Participate in Dynamic Event "Blood Mushroom Gathering" at Sandworm Lair
Participate in Dynamic Event "Dark Destroyers" at Ruins of Turayne
Participate in Dynamic Event "Stop the Mana Frenzy" at Manawastes
Participate in Dynamic Event "Requiem of Light" at the Shattered Temple
Participate in Dynamic Event "Operation: Talisman Delivery" at Akidu Valley
Participate in Dynamic Event "Festival of Fire" at Fonos Basin
Participate in Dynamic Event "Lift the Moonlight Spell" at Grayclaw Forest