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