Here is the full list of all 31 Ultros achievements.
Watch all Vistas.
Uncover every part of every area on the map.
Fully upgrade the Extractor
Gather one specimen of every critter's non-battered guts, twelve in total, in one juicy pile.
Bring the sword statue to a standstill.
Give the Host new input to analyze.
Escape Entrance without sword.
Gather one specimen of every fruit, ten in total, in one juicy pile.
Grow a plant that combines elements from all different plant species.
Feed the Enraged Moth Beast.
Take the non-violent path towards awakening Ultros.
Connect the Shaman in Pantheon of the Stars.
Connect at least one of each plant species to the living network.
Connect the Shaman in Geggamoja Refinery.
Connect the Shaman in Gärdner's Garden.
Take the violent path towards awakening Ultros.
Defeat the parasitical Host.
Lead plants into the great refinery hall for Brunzon to discover.
Connect the Shaman in Vasa's Legacy.
Connect the Shaman in Rotten Orchard.
Connect the Shaman in Infinity Lake.
Connect the three Dorok sisters.
Defeat the three Dorok sisters.
Unlock all cortex skills.
Connect the Shaman in Temple of Motherhood.
Feed the Gluttonous Feastro
Defeat Higher Suggajof Brunzon.
Defeat the Gluttonous Feastro.
Defeat Vasa, the Huntress.
Defeat the Enraged Moth Beast.
Kill an enemy with another enemy.