Here is the full list of all 19 Run The Gamut achievements.
Don't feel special, everybody gets this one.
You have completed the game on Casual Mode!
You have completed the game on Hardcore Mode!
You have completed the game on Ultra Mode!
You have completed the game with the hardest difficulty settings!
You have died 150 times attempting to pass a level and are still trying!
You skipped a level.
Attempted the game on the hardest difficulty settings. Will you be able to complete it?
You have completed the game and collected all the coins!
You have completed the game and completed all the random events!
You have completed Casual Mode in under 17 minutes time!
You have completed the game with over 100,000 points!
You have completed the game with over 250,000 points!
You have completed the game with under 100 deaths in total!
You just don't know when to quit do you? You completed the game with over 1000 deaths in total.
You have completed Act I : The Underworld.
You have completed Act II : The Overworld.
You have completed Act III : The Outerworld.
You have found Act IV : The Netherworld.