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