Here is the full list of all 43 Chronos: Before the Ashes achievements.
Put 30 Attribute Points into Vitality
Put 30 Attribute Points into Agility
Complete the Game on any Difficulty
Complete the Game on ADVENTURE
Defeat the Dreamer
Travel to Ward 16 by Way of the Mirror
Defeat the Labyrinth Guardian
Acquire the Sun Stone
Acquire the Labyrinth Scythe
Upgrade Any Weapon to Level +5
Read 10 Books or Scrolls
Exchange your Starting Weapon with a Krell Version
Return a Keepsake to the Krell King
Acquire the Shadow Stone
Defeat the Pan Guardian
Acquire the Pan Shield
Defeat the Red Widow
Solve the Flautist Riddles
Meet the Pan Flautist
Create a Rare Dragon Shard
Acquire the Pan Spear
Read 5 Books or Scrolls
Acquire the Lightning Stone
Open a Dragon Inscribed Box
Craft a Krell Mace
Defeat the Stone Golem
Acquire the Krell Shield
Acquire the Krell Hidden Weapon
Defeat the Krell Guardian
Upgrade Any Weapon
Acquire the Krell Hammer
Acquire the Fire Stone
Meet the Krell Blacksmith
Put 30 Attribute Points into Arcane
Acquire a Dragon Heart
Unlock Your First Trait
Put 30 Attribute Points into Strength
Complete the Game at age 21 or younger
Complete the Game on HEROIC
Unlock Everything
Upgrade Any Weapon to Level 9
Complete the Game in NG+ Mode