Here is the full list of all 20 The Complex achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Find an ending
Everyone dies
Sleeper agent
Find the evidence
Escort the investor out
Sacrifices must be made
Rekindle an old flame
He was alive...
Tell a joke
Reinforcements have arrived
Relationships matter
Find the hidden ending
Get over 50% relationship status with everyone