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