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