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