Here is the full list of all 34 Ashen achievements.
Defeat Sissna in the Children of Sissna mode.
Wear each relic once.
Defeat the brute near Vagrant's Rest.
Defeat the Elder Dark Sissna.
Reunite the Listener and Human hearts.
Wear the Umbral Veil.
Complete Flokir's journey.
Leap into the dark portal.
Unlock all townsfolk outfits.
Defeat the Shadow of the Ashen.
Complete Jokell's journey.
Complete Vorsa's journey.
Untangle Sissna's weave at the Palace of Lathyrus.
Complete Eila's journey.
Acquire all lanterns.
Construct all houses in Vagrant's Rest.
Hunt a roamar.
Take a ride in Eila's barrel.
Unlock all crafting specialities.
Travel the shadow pathways.
Defeat the Listener Matriarch.
Meet Kol the wildman.
Defeat Touma and Souma.
Free the Diasora pup.
Discover the secret of Contemplation.
Defeat the Elder Dark Ukkoto.
Claim Vagrant's Rest.
Hunt a Deer.
Hunt a squork.
Hunt the corb near Vagrant's Rest.
Hunt a rafet.
Defeat the Elder Dark Riak.
Defeat Riak in the Children of Sissna mode.
Acquire all Kol's armors.