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