Here is the full list of all 35 The Infectious Madness of Doctor Dekker achievements.
Excellent hint usage.
Solved in one
Eight hours played
One hundred insanity points reached
Five hundred responses revealed!
One thousand questions asked!
Four hours played
Fifty insanity points reached
Two hundred and fifty responses revealed!
Five hundred questions asked!
Two hours played
One hundred responses revealed!
Two hundred and fifty questions asked!
One hundred questions asked!
Twenty questions - well done!
Ten responses revealed!
Two thousand questions asked!
Three thousand questions asked!
Seven hundred and fifty responses revealed!
One thousand responses revealed!
Sixteen hours played
Twenty hours played
Twenty five hours played
Solved in two
Solved in three
Solved in four
Solved in five
Solved in six
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.