Here is the full list of all 23 TheNightfall achievements.
TicToc
Master of disaster
C64 demoshow
Ice at midnight
Nice meal
Retro Gamer
Retro Master
Retro King
Fragman Gamer
Fragman Master
Fragman King
No friends in the neighborhood
Typical gamer
Thirsty
To loud
Why?
Coffee junky
Bad vibrations
Evil clowns in the dark
Don´t trust the dolls
Find 5 hidden pumpkins during Halloweentime.
Find 10 hidden pumpkins during Halloweentime.
Find all 20 hidden pumpkins during Halloweentime.