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