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