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