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