Here is the full list of all 19 Mustache in Hell achievements.
Defeat Cereberus
Defeat Ciacco
Defeat the giant spiders
Defeat Kraken
Defeat Charon
Got the Atari joystick
Got the NES controller
Got the Genesis controller
Got the SNES controller
Got the Game Boy
Got all controlles
Read all books
Reach the Cerberus without get a hit
Beat the first three areas of The Fall of Guilt with only the pistol
Complete the Styx Waters without being hit by a saw
Don't die facing the Kraken
End the first five areas of the Tombs without using secondary weapon
Don't die facing the Charon
Defeating Cerberus without sprinting