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