Here is the full list of all 6 TimeTekker achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Achieved 10,000 points!
Earned the maximum possible multiplier on Merciless difficulty!
Achieved 2500 points and unlocked the Merciless difficulty level!
Achieved 750 points and unlocked the Brutal difficulty level!
Annoyed the hero on the main menu screen!
Launched the game