Here is the full list of all 34 Sphinx and the Cursed Mummy achievements.
Fulfill the Ancient Prophecy of Ra
Increase your health to a grand total of 12 Gold Ankhs
Find all the trinkets under the rich farm soil
Beat your best time in the Heliopolis obstacle course
Complete the Abydos Museum's Natural History collection
Return all the Abydos Jewels to their rightful place
Complete the fourth chapter
Complete the third chapter
Complete the second chapter
Given by the Abydos Museum for collecting 30 monsters
Find the Hands of Amun
Complete the first chapter
Prove your mastery of the Blowpipe
Given by the Abydos Museum for collecting 20 monsters
Given by the Abydos Museum for collecting 10 monsters
Uncover all the Atun Discs in Heliopolis
Match each pair of items behind the doors to win this game
Awarded only to those who manage to beat the gauntlet
Complete the Heliopolis athletics course in 69 seconds or less
Equip the Dark Stone of Invisibility
Make the Riverside Farm habitable again
Some of the best things in life are hidden in plain sight
Find the blowpipe
Complete the Heliopolis obstacle course in 77 seconds or less
Find the Wings of Ibis
Complete the Heliopolis swimming course
Obtain a zip line handle
Test your skills in the mystical game of sequences
Find the Shield of Osiris
Try to stay fashionable around palace
Find the Blade of Osiris
Share your feelings with your fellow apprentice
Some shortcuts will bring unexpected consequences
Obtain all the precious Onyx Scarabs in the Castle of Uruk