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.
Read the last journal entry.
Defeat the boss in the Land of Darkness.
Open your very first gold chest.
Defeat the boss in Castle Hamson.
Defeat the boss in the Forest Abkhazia.
Defeat the boss in the Maya.
Have one piece of equipment in every item slot.
Find all blueprints (purchase not necessary).
Have one rune equipped in every item slot.
Find all the runes (purchase not necessary).
Beat the game... twice.
Play the game for at least 20 hours.
Defeat the last boss.
Reach level 50 or higher.
Die 20 times or more.
Earn your very first Enchantress rune.
Choose a hero with no traits.
Put at least one point in every skill in the manor.
Defeat all the minibosses.
Kill a chicken.
Use the special class at least once.
Beat one of the clown's games at least once.
Defeat the brothers.
Defeat the trademarked chemical.
Defeat the son.
Defeat the doppleganger.
Defeat the asteroids.
Mock the traitor.
WITHOUT using the Architect, complete the game dying 15 times or less