Here is the full list of all 19 Angry Video Game Nerd Adventures achievements.
Find all S*** Pickles
Find all the cameos
Find Craig
Enter a cheat code
Find all playable characters
Found Matthew Lentz
Beat the game on "Old School" or higher
Die 1000 times
Kill Naggi
Beat the game on "Normal" or higher
Kill Santa
Drink 100 beers
Ride the Fire shark
Die 100 times
Collect 200 1ups
Beat the game on "Hard as Balls" or higher
Beat the game on "Impossible" or higher
Beat the game on "YOLO"
Beat the game over Halloween weekend on Normal or Higher difficulty