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