Here is the full list of all 54 Fallen Enchantress: Legendary Heroes achievements.
Play for 40 hours.
Win by defeating all of your opponents.
Win as Resoln.
Recruit Gallowman
Recruit Nen Ratcatcher
Win by forging an alliance with all players.
Win as Pariden.
Reach level 15 with a champion.
You've managed to slay Torax!
Play for 20 hours.
Make 1000 gildar from selling items in shops.
Recruit Ascian
Win by completing the Master Quest.
Win and have at least 3,000 population.
Complete 10 quests in a single game.
Not since Peter MacNicol has one been slain!
Defeat a faction.
Get a city to level 5 in one game.
Play for 10 hours.
You defeated a sovereign in battle!
You have captured an enemy city!
Control 5 cities in a single game.
Play for 5 hours.
Tap 10 resources in a single game.
Design a unit.
Recruit Tuatha
Reach level 5 with a champion.
Buy an item from a shop.
Explore 10 goodie huts in a single game.
You killed a monster!
You have defeated an army!
Your Fame has lead a hero to your cause.
Complete a quest.
All nations start with one.
Create a custom sovereign.
You've managed to slay Abeix!
You've managed to slay Delin!
You've managed to slay Morian!
You've managed to slay Vetrar!
Awarded for completion of the Legendary Hero scenario.
Win by casting the Spell of Making.
Win by having the highest score by the turn limit.
Win as Altar.
Win as Gilden.
Win as Tarth.
Win as Kraxis.
Win as Magnar.
Win as Yithril.
Play for 100 hours.
Recruit Mausolos
Recruit Raza the Wild
Recruit Kasst
Win as Capitar.
Win as Umber.