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