Here is the full list of all 29 Rogue Legacy achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
WITHOUT using the Architect, complete the game dying 15 times or less
Beat the game... twice.
Defeat the brothers.
Mock the traitor.
Defeat the son.
Find all blueprints (purchase not necessary).
Defeat the asteroids.
Defeat the trademarked chemical.
Defeat the doppleganger.
Play the game for at least 20 hours.
Defeat the last boss.
Beat one of the clown's games at least once.
Defeat the boss in the Land of Darkness.
Defeat the boss in the Maya.
Defeat the boss in the Forest Abkhazia.
Put at least one point in every skill in the manor.
Find all the runes (purchase not necessary).
Defeat all the minibosses.
Use the special class at least once.
Read the last journal entry.
Have one rune equipped in every item slot.
Defeat the boss in Castle Hamson.
Open your very first gold chest.
Reach level 50 or higher.
Kill a chicken.
Have one piece of equipment in every item slot.
Choose a hero with no traits.
Earn your very first Enchantress rune.
Die 20 times or more.