Here is the full list of all 17 Abyss Odyssey achievements.
Unlock the Pincoya.
Defeat the Living Creature.
Defeat Paganini, the Demon Violinist.
Capture a level 10 enemy.
Defeat the Warlock.
Uncover the Warlock's secret.
Defeat the shopkeeper.
Finish the prologue.
Defeat Verbum Dei.
Capture a level 25 enemy.
Capture a level 40 enemy.
Equip Katrien with 3 fully upgraded special attacks.
Equip the Ghost Monk with 3 fully upgraded special attacks.
Equip the Pincoya with 3 fully upgraded special attacks.
Defeat the Warlock in nightmare difficulty, "Coop Friendly Fire" must be on.
Defeat the Golem.
Win 5 online versus matches in one session.