Full list of all 59 Deepening Fire achievements.
The base game contains 54 achievements, and there is 1 DLC pack containing 5 achievements.
Activated a Firebrand for the first time
Tasted the burn
Unlocked a rare past
Locked a rare past
Committed suicide and obtained the Emblem of Inversion
Stunned the Queen
Achieved the ending: Enter the Ark
Achieved the ending: The Other Coast
Defeated Defender
Defeated Irracil's Shadow
Defeated Afflicted Noble
Defeated Irene, Blessed Knight
Defeated Stillborn
Defeated Leibniz, the Phantom
Defeated Mockingbird
Defeated Moon Kindler
Defeated Colossus of Mercy
Defeated the Beautician
Defeated Unending Fire
Defeated Irracil, the Radiant
Defeated Spirits of Blind Hawk & Limb-taken Wolf
Defeated Gatekeeper
Defeated Gryn and Haelyn
Defeated Queen Archimedes
Defeated the Fisher
Defeated Leibniz, the False
Defeated Giant Dog
Defeated Haelyn, the White Prince
Defeated Ancient Defender
Helped the minister specter clean up the chapel
Saved the music box
Fixed the music box with the brightstone movement
Saved the magic mirror
Gave the magic mirror carte blanche and got a rare haircut
Saved the wingling
Traded all of the wingling's items
Obtained Florie's doll
Completed 3 of Aogiri's trainings
Completed all of Aogiri's trainings
Aogiri left the secret garden
Found Aogiri's body
Collected all sunblooms
Collected all peculiar eyeballs
Collected all fire seeds and dark fire seeds
Collected all weapons
Collected all armor
Collected all Firebrands
Upgraded fist affinity to its max
Upgraded sword affinity to its max
Upgraded blade affinity to its max
Upgraded axe affinity to its max
Upgraded spear affinity to its max
Upgraded staff affinity to its max
Obtained all achievements
Enkindle the Ruining Fire
Unlock new appearance editing options
Defeated all ruinous invaders
Clear the game with the Ruining Fire enkindled immediately after you reach Secret Garden
Awooooo!