Here is the full list of all 40 The Forgotten City achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Reach the best ending with the smallest number of loops
Free the captive and shoot her captor with your gun
Topple 10 peeled statues by kicking others into them
Die from hornet stings
Finish the game without looping through time once
Reach Ending 4 of 4
Assemble as many people as possible in the Museum
Talk your way through every possible confrontation
Intimidate the creator of The Golden Rule
Confront the creator of The Golden Rule
Loop through time ten times
Reach Ending 3 of 4
Have Duli released from his cell
Enter a villa with a daring leap
Allow Fabia to die in the collapsing temple
Reach Ending 1 of 4
Help Galerius romance Equitia
Use Photo Mode
Get rejected by Aurelia
Reach Ending 2 of 4
Find all three missing persons
Save Ulpius's life
Lie 10 times
Solve Vergil's problem
Enter the upper cistern in an unconventional way
Read 10 different grafitti
Find treasure using the golden bow
Dodge 3 boulders
Discover Underworld icons Sisyphus, Tantalus, Ixion and the Belide
Learn the true identity of the stranger by the river
Survive the Palace
Gild your first thing
Save Fabia's life
Save Iulia's life
Loop through time once
Pick up the sponge on a stick
Steal 2000 coins after the Golden Rule is broken
Trigger The Golden Rule by stealing 5 times
Discover what lies beneath the city
Skip the city tour