Here is the full list of all 35 The Infectious Madness of Doctor Dekker achievements.
Solved in five
Five hundred insanity points reached
Zero hints, and you absolutely didn't cheat at all.
Solved in four
Twenty five hours played
Solved in two
Three thousand questions asked!
Solved in six
Three hundred insanity points reached
Twenty hours played
It's a bit hinty in here.
Solved in one
Excellent hint usage.
Sixteen hours played
One thousand responses revealed!
Two thousand questions asked!
Solved in three
Two hundred insanity points reached
You made Nathan sing a song.
Seven hundred and fifty responses revealed!
One hundred and fifty insanity points reached
One hundred insanity points reached
Five hundred responses revealed!
One thousand questions asked!
Eight hours played
Fifty insanity points reached
Two hundred and fifty responses revealed!
Five hundred questions asked!
Four hours played
Two hours played
Two hundred and fifty questions asked!
One hundred responses revealed!
One hundred questions asked!
Twenty questions - well done!
Ten responses revealed!