Here is the full list of all 31 The Dark Eye: Memoria achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Complete Chapter Eight.
Make your decision.
Complete Chapter Seven.
Complete Chapter Five.
Complete Chapter Six.
Collect all elementals.
Give all items to Xerxes.
Complete Chapter Four.
Ashes to ashes, stone to dust.
Complete Chapter Three.
Defeat the spider.
Find the fox within the labyrinth.
Complete Chapter Two.
Give Bryda the wrong astral accumulator.
Shards crack loudly.
Do you have the guts to start an argument?
Turn the pig on the grill.
Complete Chapter One.
Does Bryda know who you really are?
Try to tear down the wall with the golem.
Do You Like Riddles?
Find out who of the adventuring party lies at the first try.
Tread lightly.
Catch the rabbit at the first try.
The forest is my home.
Stone, dust, stone, dust.
Throw all items into the chasm.
Persuade the spirit of air to help you straight away.
Adjust the horns towards the spheres.
Find the Caverns of Fail.