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 Humanity.
Corrupt seven Abilities.
Defeat Nyarlathotep & The Shining Trapezohedron.
Find all Perks.
Destroy seven Elder Shards.
Collect 500,000 Shards.
Defeat Nyarlathotep.
Equip three Perks simultaneously.
Defeat Legion & Salvation.
Defeat all Minibosses.
Unlock all Abilities.
Defeat Hysteria.
Destroy your first Elder Shard.
Corrupt your first Ability.
Defeat Dominion.
Collect 10,000 Shards.
Equip your first Perk.
Defeat your first Miniboss.
Survive your first horde.
Unlock your first Ability.