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