Here is the full list of all 25 Anima: Gate of Memories - there are The Nameless Chronicles achievements.
Help the Priest of Erynes.
Defeat Druaga.
Make Gaudemus create something for you.
Free the prisoner from his prison.
Defeat Red Lady.
Reach Arcane.
Finish the prologue.
Unlock the Secret Ending.
Finish the game obtaining the True Ending.
Finish the game obtaining the Alternative Ending.
Finish the game in New Game+.
Find all the hidden items in Arcane.
Defeat the Secret Boss.
Reach Level 16.
Get the rank of Grand Maister in the Cathedral of Erynes.
Finish all possible conversations with Death.
Find all the fragments of Velez’s Soul.
Obtain the Thanathos Nekrom.
Unlock the access to the Inner Halls of Arcane.
Defeat Ergo and The Bearer in the Nexus.
Defeat the Shadow of the Nameless.
Defeat the three guardian shadows.
Defeat Ergo and The Bearer in Erynes.
Defeat Nascal the Puppetmaster.
Defeat Rametek.