Here is the full list of all 34 Ashen achievements.
Defeat the Elder Dark Riak.
Defeat Riak in the Children of Sissna mode.
Acquire all Kol's armors.
Wear the Umbral Veil.
Wear each relic once.
Defeat the Elder Dark Sissna.
Defeat Sissna in the Children of Sissna mode.
Complete Flokir's journey.
Reunite the Listener and Human hearts.
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.
Unlock all crafting specialities.
Travel the shadow pathways.
Meet Kol the wildman.
Hunt a squork.
Defeat the Listener Matriarch.
Take a ride in Eila's barrel.
Defeat Touma and Souma.
Free the Diasora pup.
Discover the secret of Contemplation.
Defeat the Elder Dark Ukkoto.
Defeat the brute near Vagrant's Rest.
Hunt the corb near Vagrant's Rest.
Hunt a Deer.
Claim Vagrant's Rest.
Hunt a rafet.