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