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