Here is the full list of all 20 Sundered achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Defeat Nyarlathotep & The Shining Trapezohedron.
Destroy seven Elder Shards.
Defeat Nyarlathotep.
Find all Perks.
Destroy your first Elder Shard.
Survive your first horde.
Unlock your first Ability.
Defeat your first Miniboss.
Corrupt your first Ability.
Corrupt seven Abilities.
Unlock all Abilities.
Equip three Perks simultaneously.
Defeat Dominion.
Defeat Hysteria.
Defeat Legion & Salvation.
Defeat Humanity.
Equip your first Perk.
Collect 10,000 Shards.
Collect 500,000 Shards.
Defeat all Minibosses.