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