Here is the full list of all 12 Red Goddess: Inner World achievements.
Complete Act I.
Complete Act II.
Complete Act III.
Complete Act IV.
Perform 60 combos.
Perform 100 combos.
Destroy 30 enemies using possession ability.
Destroy 15 enemies using Rage's special melee attack.
Destroy 15 enemies using Fear's special melee attack.
Collect 300 gold.
Collect 500 gold.
Overcome your demons.