Here is the full list of all 51 Pyre achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Prevail in a Rite with six or more Titan Stars active (Campaign)
Prevail in a Rite with 12 Titan Stars active (Campaign)
Prevail in a Rite with three or more Titan Stars active (Campaign)
Complete your quest for freedom (Campaign)
Use Scribe Snuff to reset an exile's Masteries (Campaign)
Suffer defeat in a Liberation Rite (Campaign)
Prevail in a Rite in no more than three dousings (Campaign)
Using Volfred, deal 200 Pyre Damage (Campaign)
During a Rite, fling the Orb at an adversary, then banish them within two sec. (Campaign)
Spend 1,000 Sol in the Slugmarket (Campaign)
Prevail in a Rite against a CPU opponent while you have less than 10 Pyre Health (Versus Mode with default Masteries, Talismans, Pyre Health)
Prevail at the Isle of Khaylmer using Ti'zo and Messenger Imp (Versus Mode)
Prevail using Sandra, Tamitha, and Udmildhe (Versus Mode)
Prevail using Rukey, Barker, and Dalbert (Versus Mode)
Complete a Rite against a CPU opponent (Versus Mode)
Prevail using Volfred, Ti'zo, and Oralech (Versus Mode)
Complete a Rite against another mortal (Versus Mode)
Complete three Feats of Glory (Campaign)
Unlock every chapter in the Book of Rites (Campaign)
Find an exile for each of the different masks (Campaign)
Liberate any three exiles from your party (Campaign)
Do Vocations 10 times (Campaign)
Using Ti'zo, deal 200 Pyre Damage (Campaign)
During a Rite, banish three adversaries with a single Aura Cast (Campaign)
Prevail in a Rite against each of the other triumvirates (Campaign)
Prevail in a Rite at each of the Celestial Landmarks (Campaign)
Using Bertrude, deal 200 Pyre Damage (Campaign)
Check 50 different pages in the Book of Rites (Campaign)
While flying, bump into five different adversaries' wagons (Campaign)
Using Hedwyn, deal 200 Pyre Damage (Campaign)
While flying, interact with 10 different observation points (Campaign)
Using Pamitha, deal 200 Pyre Damage (Campaign)
Complete five Scribe Trials in the Beyonder Crystal (Campaign)
Using Sir Gilman, deal 200 Pyre Damage (Campaign)
During a Rite, douse the adversary's Pyre by 40 health or more (Campaign)
Achieve Rank 5 with any exile (Campaign)
Upgrade a Talisman to Rank 20 (Campaign)
Initiate 20 different conversations in the blackgwagon (Campaign)
Prevail in a Liberation Rite (Campaign)
Prevail in a Rite using Jodariel and Pamitha (Campaign)
Using the Stowaway, deal 200 Pyre Damage (Campaign)
Complete two Scribe Trials in the Beyonder Crystal (Campaign)
Using Jodariel, deal 200 Pyre Damage (Campaign)
Complete a Practice Rite in the Beyonder Crystal (Campaign)
Prevail in a Rite without your Pyre taking damage (Campaign)
Using Rukey, deal 200 Pyre Damage (Campaign)
Use the White Lute to play a tune (Campaign)
Begin your quest for freedom (Campaign)
Prevail in a Rite against a Master-level CPU opponent (Versus Mode, default Talismans and Masteries)
Prevail against a Master CPU opponent with six or more Titan Stars active (Versus Mode with default Masteries, Talismans, Pyre Health)
Complete your quest for freedom (Campaign, True Nightwing difficulty)