Here is the full list of all 35 One Step From Eden achievements.
Beat Hell Mode 14
Beat the game without collecting any Artifacts
Have 8 pacts at the same time
Defeat tier 4 Shopkeeper
Beat Serif and get sent back
Execute Serif
Beat the game without taking any spells
Beat the game with every character
Spare Terrable
Defeat tier 4 Violette
Defeat tier 4 Terra
Defeat tier 4 Hazel
Cover the entire field in flames
Defeat tier 4 Selicy
Defeat tier 4 Shiso
Kill a hostage with the Devour spell
Have 0 Max Mana
Execute Terrable
Defeat tier 4 Gunner
Win a boss fight with 1 HP
Reach the Gate
Defeat tier 4 Reva
Defeat tier 4 Saffron
Have over 200 cardtridges in your deck
Kill the last enemy with the Fadeaway spell
Have at least 16 broken tiles at the same time
Kill Gunner or Shiso with a Slashfik spell
Have a spell from every Focus in your deck
Upgrade the same spell 4 times
Have 1 Spell in your deck
Get a Calamity spell
Win a battle without using a Spell or Weapon
Have over 9,999 Shield
Destroy a Self Defense hazard
Cast 10 Jams in one battle