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