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