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