Here is the full list of all 32 Curse of the Assassin achievements.
Find all the artwork in Curse of the Assassin
Become possessed by an ultimate boss
Complete the gamebook in Classic Mode
Laugh hysterically with Esplandian
Return a cry three times when out at sea
Successfully report back to the Head Gaoler
Meet all the creatures from folklore and legend
Fool the mighty Coca Rabixa
Find the best weapon in the gamebook
Defeat the leader of the Hombre Peces
Find the best armour in the gamebook
Visit all the taverns in the story
Successfully use your hunting skills
Offer your life for another
Rescue two people very close to you
Return a ring to the rightful owners
Recruit all members of the Death Hawks
Find out the location of the Jewel of Orlandes
Complete the gamebook in Adventurer Mode
Hear the 'Endecha de la Sangre'
Save a companion from some watery rapids
Find out the meaning behind the 'breadbasket of Orlandes'
Complete the gamebook in Casual Mode
Roll 3 sixes in one roll
Purify the water in a well
Meet a Sanziana and receive a special gift
Discover a dastardly plot
Roll 3 ones in one dice roll
Steal a sheep
Receive a threatening letter
Receive a special blessing
Learn the secrets of Coyote Lore