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.
Find all blueprints (purchase not necessary).
Defeat the brothers.
Beat the game... twice.
Defeat the asteroids.
Play the game for at least 20 hours.
Defeat the trademarked chemical.
Defeat the son.
Beat one of the clown's games at least once.
Put at least one point in every skill in the manor.
Use the special class at least once.
Defeat the last boss.
Defeat the boss in the Land of Darkness.
Defeat all the minibosses.
Find all the runes (purchase not necessary).
Read the last journal entry.
Defeat the boss in the Maya.
Defeat the doppleganger.
Defeat the boss in the Forest Abkhazia.
Reach level 50 or higher.
Have one rune equipped in every item slot.
Have one piece of equipment in every item slot.
Defeat the boss in Castle Hamson.
Kill a chicken.
Open your very first gold chest.
Die 20 times or more.
Choose a hero with no traits.
Earn your very first Enchantress rune.