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