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