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