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
Find all blueprints (purchase not necessary).
Beat one of the clown's games at least once.
Defeat all the minibosses.
Beat the game... twice.
Mock the traitor.
Defeat the brothers.
Defeat the asteroids.
Find all the runes (purchase not necessary).
Defeat the son.
Play the game for at least 20 hours.
Read the last journal entry.
Defeat the boss in the Land of Darkness.
Defeat the boss in the Forest Abkhazia.
Use the special class at least once.
Defeat the trademarked chemical.
Defeat the boss in the Maya.
Have one rune equipped in every item slot.
Defeat the doppleganger.
Have one piece of equipment in every item slot.
Open your very first gold chest.
Die 20 times or more.
Choose a hero with no traits.
Kill a chicken.
Earn your very first Enchantress rune.
Defeat the last boss.
Defeat the boss in Castle Hamson.
Put at least one point in every skill in the manor.
Reach level 50 or higher.