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