Here is the full list of all 19 Ben and Ed achievements.
Kill 20 chicken.
Reach a checkpoint in one piece.
Finish the tutorial.
Beat Hans' first masterpiece.
Beat Hans' second masterpiece.
Collect 20% of all candymeat.
Collect 50% of all candymeat.
Collect 100% of all candymeat.
Beat 5 level unharmed.
Beat 12 level unharmed.
Beat all level unharmed.
Kill 50 chicken.
Kill 100 chicken.
Beat Hans.
Reunite with your friend.
Finish the game.
Impress 200 viewers.
Impress 700 viewers.
Impress 1100 viewers.