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.
WITHOUT using the Architect, complete the game dying 15 times or less
Mock the traitor.
Defeat the brothers.
Defeat the trademarked chemical.
Find all blueprints (purchase not necessary).
Find all the runes (purchase not necessary).
Play the game for at least 20 hours.
Beat one of the clown's games at least once.
Defeat the son.
Defeat the asteroids.
Defeat the doppleganger.
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 Land of Darkness.
Defeat all the minibosses.
Defeat the boss in the Maya.
Defeat the boss in the Forest Abkhazia.
Open your very first gold chest.
Defeat the boss in Castle Hamson.
Use the special class at least once.
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.
Kill a chicken.
Earn your very first Enchantress rune.
Die 20 times or more.
Choose a hero with no traits.