Here is the full list of all 23 Absolver trophies - there are 6 bronze, 9 silver, 7 gold and 1 platinum.
Earn all trophies
Master all attacks with one character
Kill all bosses in their last level with one character
Unlock all fighting styles with one character
Unlock Calbot
Reach Game Mode Level 100
Create a school
Become a disciple of your school
Kill 100 Players Character (Any Character)
Reach Game Mode Level 5
Kill your opponent with his own weapon in 1v1
Win 1 PVP Duel
Become an Absolver
Kill Risryn
Open all Cairns with one character
Join a school
Kill Cargal & Kilnor
Have Cargal kill Kilnor (or the opposite)
Kill all marked ones with one character
Master 1 new Attack
Push AI off ledge
Loot 1 weapon
Kill Kuretz