Here is the full list of all 22 Etrian Odyssey HD achievements.
Reached the Fifth Stratum.
Unlocked the Hexer class.
Obtained more than 250,000 Ental.
Reached the Fourth Stratum.
Completed the quest "The bandit's treasure".
Retired an adventurer.
Let an adventurer rest.
Unlocked the Ronin class.
Defeated a boss in a single turn.
Reached the Third Stratum.
Dealt 1,000 damage with a single hit.
Reached the Second Stratum.
Reached the First Stratum.
Obtained all other achievements.
Reached the Sixth Stratum.
Defeated the boss of the Sixth Stratum on Expert difficulty.
Defeated the Etreant.
Defeated the Yggdrasil Core.
Defeated an Yggdrasil Bud, Yggdrasil Sprout, and Yggdrasil Clover.
Defeated the Wyrm.
Defeated the Drake.
Defeated the Dragon.