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