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