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
Assemble as many people as possible in the Museum
Talk your way through every possible confrontation
Reach Ending 4 of 4
Intimidate the creator of The Golden Rule
Confront the creator of The Golden Rule
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
Lie 10 times
Allow Fabia to die in the collapsing temple
Help Galerius romance Equitia
Loop through time ten times
Reach Ending 3 of 4
Have Duli released from his cell
Discover Underworld icons Sisyphus, Tantalus, Ixion and the Belide
Reach Ending 1 of 4
Reach Ending 2 of 4
Find all three missing persons
Enter the upper cistern in an unconventional way
Dodge 3 boulders
Learn the true identity of the stranger by the river
Solve Vergil's problem
Find treasure using the golden bow
Trigger The Golden Rule by stealing 5 times
Steal 2000 coins after the Golden Rule is broken
Get rejected by Aurelia
Read 10 different grafitti
Survive the Palace
Gild your first thing
Save Fabia's life
Discover what lies beneath the city
Save Ulpius's life
Save Iulia's life
Skip the city tour
Pick up the sponge on a stick
Enter a villa with a daring leap
Loop through time once
Use Photo Mode