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